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AUSCERT External Security Bulletin Redistribution
ESB-2017.1002
Cisco ASA Software Multiple Vulnerabilities
20 April 2017
===========================================================================
AusCERT Security Bulletin Summary
---------------------------------
Product: Cisco ASA Software
Publisher: Cisco Systems
Operating System: Cisco
Impact/Access: Denial of Service -- Remote/Unauthenticated
Provide Misleading Information -- Remote/Unauthenticated
Resolution: Patch/Upgrade
CVE Names: CVE-2017-6610 CVE-2017-6609 CVE-2017-6608
CVE-2017-6607 CVE-2017-3793
Original Bulletin:
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-dns
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-xauth
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-tls
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-norm
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-ipsec
Comment: This bulletin contains five (5) Cisco Systems security advisories.
- --------------------------BEGIN INCLUDED TEXT--------------------
Cisco Security Advisory
Cisco ASA Software DNS Denial of Service Vulnerability
High
Advisory ID:
cisco-sa-20170419-asa-dns
First Published:
2017 April 19 16:00 GMT
Version 1.0:
Final
Workarounds:
No workarounds available
Cisco Bug IDs:
CSCvb40898
CVE-2017-6607
CWE-399
CVSS Score:
Base 8.1, Temporal 8.1
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:X/RL:X/RC:X
CVE-2017-6607
CWE-399
Summary
A vulnerability in the DNS code of Cisco ASA Software could allow an
unauthenticated, remote attacker to cause an affected device to reload or
corrupt the information present in the device's local DNS cache.
The vulnerability is due to a flaw in handling crafted DNS response
messages. An attacker could exploit this vulnerability by triggering a DNS
request from the Cisco ASA Software and replying with a crafted response. A
successful exploit could cause the device to reload, resulting in a denial
of service (DoS) condition or corruption of the local DNS cache
information.
Note: Only traffic directed to the affected device can be used to exploit
this vulnerability. This vulnerability affects Cisco ASA Software
configured in routed or transparent firewall mode and single or multiple
context mode. This vulnerability can be triggered by IPv4 and IPv6 traffic.
Cisco has released software updates that address this vulnerability. There
are no workarounds that address this vulnerability.
This advisory is available at the following link:
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-dns
Affected Products
Vulnerable Products
This vulnerability affects Cisco ASA Software running on the following
products:
Cisco ASA 1000V Cloud Firewall
Cisco ASA 5500 Series Adaptive Security Appliances
Cisco ASA 5500-X Series Next-Generation Firewalls
Cisco ASA Services Module for Cisco Catalyst 6500 Series Switches and
Cisco 7600 Series Routers
Cisco Adaptive Security Virtual Appliance (ASAv)
Cisco Firepower 9300 ASA Security Module
Cisco ISA 3000 Industrial Security Appliance
Refer to the Fixed Software section of this security advisory for more
information about affected releases.
Cisco ASA Software is affected by this vulnerability if at least one DNS
server IP address is configured under a DNS server group. This can be
configured as part of the default DNS server group (DefaultDNS) or a
user-defined DNS server group.
To determine whether a DNS server IP address is configured, use the show
running-config dns server-group command and verify that the name-server
parameter includes an IP address.
The following example shows a Cisco ASA Software appliance that is
configured with the DNS server IP 192.168.1.1 as part of the DefaultDNS
server group.
ciscoasa# show running-config dns server-group
DNS server-group DefaultDNS
name-server 192.168.1.1
.
.
.
Note: By default, the DNS name-server value is not configured in any DNS
server group.
Determining the Running Software Release
To determine whether a vulnerable release of Cisco ASA Software is running
on an appliance, administrators can use the show version command. The
following example shows the results for an appliance running Cisco ASA
Software Release 9.2(1):
ciscoasa# show version | include Version
Cisco Adaptive Security Appliance Software Version 9.2(1)
Device Manager Version 7.4(1)
Customers who use Cisco Adaptive Security Device Manager (ASDM) to manage
devices can locate the software release in the table that appears in the
login window or the upper-left corner of the Cisco ASDM window.
Products Confirmed Not Vulnerable
No other Cisco products are currently known to be affected by this
vulnerability.
Workarounds
There are no workarounds that address this vulnerability.
Fixed Software
Cisco has released free software updates that address the vulnerability
described in this advisory. Customers may only install and expect support
for software versions and feature sets for which they have purchased a
license. By installing, downloading, accessing, or otherwise using such
software upgrades, customers agree to follow the terms of the Cisco
software license:
http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html
Additionally, customers may only download software for which they have a
valid license, procured from Cisco directly, or through a Cisco authorized
reseller or partner. In most cases this will be a maintenance upgrade to
software that was previously purchased. Free security software updates do
not entitle customers to a new software license, additional software
feature sets, or major revision upgrades.
When considering software upgrades, customers are advised to regularly
consult the advisories for Cisco products, which are available from the
Cisco Security Advisories and Alerts page, to determine exposure and a
complete upgrade solution.
In all cases, customers should ensure that the devices to be upgraded
contain sufficient memory and confirm that current hardware and software
configurations will continue to be supported properly by the new release.
If the information is not clear, customers are advised to contact the Cisco
Technical Assistance Center (TAC) or their contracted maintenance
providers.
Customers Without Service Contracts
Customers who purchase directly from Cisco but do not hold a Cisco service
contract and customers who make purchases through third-party vendors but
are unsuccessful in obtaining fixed software through their point of sale
should obtain upgrades by contacting the Cisco TAC:
http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.html
Customers should have the product serial number available and be prepared
to provide the URL of this advisory as evidence of entitlement to a free
upgrade.
Fixed Releases
In the following table, the left column lists major releases of Cisco ASA
Software. The right column indicates whether a major release is affected by
the vulnerability described in this advisory and the first release that
includes the fix for this vulnerability.
Cisco ASA Software First Fixed Release
Major Release
Prior to 9.0^1 Affected, migrate to 9.1(7.12) or later
9.0^1 Affected, migrate to 9.1(7.12) or later
9.1 9.1(7.12) or later
9.2 9.2(4.18) or later
9.3^1 Affected, migrate to 9.4(3.12) or later
9.4 9.4(3.12) or later
9.5 9.5(3.2) or later
9.6 9.6(2.2) or later
9.7 Not affected
9.8 Not affected
^1 Cisco ASA Software releases prior to 9.1 and Cisco ASA Software Release
9.3 have reached end-of-software maintenance. Customers should migrate to a
supported release.
Note: It is possible that certain fixed software releases for this
vulnerability are affected by a bug described in Cisco Field Notice
FN-64291 where a security appliance may fail to pass traffic after 213 days
of uptime. Customers should review this notice before determining a course
of action for addressing the vulnerability described in this advisory. The
issue described in the Cisco Field Notice is not a security vulnerability.
Exploitation and Public Announcements
The Cisco Product Security Incident Response Team (PSIRT) is not aware of
any public announcements or malicious use of the vulnerability that is
described in this advisory.
Source
This vulnerability was found during internal testing.
Cisco Security Vulnerability Policy
To learn about Cisco security vulnerability disclosure policies and
publications, see the Security Vulnerability Policy. This document also
contains instructions for obtaining fixed software and receiving security
vulnerability information from Cisco.
Subscribe to Cisco Security Notifications
Subscribe
Action Links for This Advisory
Cisco IOS and IOS-XE Software Domain Name System Memory Corruption
URL
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/
cisco-sa-20170419-asa-dns
Revision History
Version Description Section Status Date
1.0 Initial public release. Final 2017-April-19
Show Less
Legal Disclaimer
THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND
OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT
OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES
THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.
A standalone copy or paraphrase of the text of this document that omits the
distribution URL is an uncontrolled copy and may lack important information
or contain factual errors. The information in this document is intended for
end users of Cisco products.
Cisco Security Vulnerability Policy
To learn about Cisco security vulnerability disclosure policies and
publications, see the Security Vulnerability Policy. This document also
contains instructions for obtaining fixed software and receiving security
vulnerability information from Cisco.
===
Cisco Security Advisory
Cisco ASA Software Internet Key Exchange Version 1 XAUTH Denial of Service
Vulnerability
High
Advisory ID:
cisco-sa-20170419-asa-xauth
First Published:
2017 April 19 16:00 GMT
Version 1.0:
Final
Workarounds:
No workarounds available
Cisco Bug IDs:
CSCuz11685
CVE-2017-6610
CWE-399
CVSS Score:
Base 7.7, Temporal 7.7
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H/E:X/RL:X/RC:X
CVE-2017-6610
CWE-399
Summary
A vulnerability in the Internet Key Exchange Version 1 (IKEv1) XAUTH code
of Cisco ASA Software could allow an authenticated, remote attacker to
cause a reload of an affected system.
The vulnerability is due to insufficient validation of the IKEv1 XAUTH
parameters passed during an IKEv1 negotiation. An attacker could exploit
this vulnerability by sending crafted parameters.
Note: Only traffic directed to the affected system can be used to exploit
this vulnerability. This vulnerability only affects systems configured in
routed firewall mode and in single or multiple context mode. This
vulnerability can be triggered by IPv4 or IPv6 traffic. A valid IKEv1 Phase
1 needs to be established to exploit this vulnerability, which means that
an attacker would need to have knowledge of a pre-shared key or have a
valid certificate for phase 1 authentication.
Cisco has released software updates that address this vulnerability. There
are no workarounds that address this vulnerability.
This advisory is available at the following link:
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-xauth
Affected Products
Vulnerable Products
This vulnerability affects Cisco ASA Software running on the following
products:
Cisco ASA 1000V Cloud Firewall
Cisco ASA 5500 Series Adaptive Security Appliances
Cisco ASA 5500-X Series Next-Generation Firewalls
Cisco ASA Services Module for Cisco Catalyst 6500 Series Switches and
Cisco 7600 Series Routers
Cisco Adaptive Security Virtual Appliance (ASAv)
Cisco ASA for Firepower 9300 Series
Cisco ISA 3000 Industrial Security Appliance
Refer to the Fixed Software section of this security advisory for more
information about affected releases.
Cisco ASA Software is affected by this vulnerability if the system is
configured to terminate remote access IKEv1 VPN connections using IPsec
client and XAUTH is used for user authentication.
Cisco ASA Software is not affected by this vulnerability if the system is
configured to terminate the following VPN connections:
Clientless SSL
AnyConnect SSL
Internet Key Exchange Version 2 (IKEv2) AnyConnect
LAN-to-LAN VPN
Layer 2 Tunneling Protocol (L2TP)-IPsec VPN
To determine whether a Cisco ASA Software appliance is configured to
terminate IKEv1 remote access VPN connections, a dynamic crypto map must be
configured for at least one interface. Administrators should use the show
running-config crypto map | include interface|dynamic command and verify
that the output includes a dynamic crypto map. The following example shows
a crypto map named outside_map configured on the outside interface:
ciscoasa# show running-config crypto map | include interface|dynamic
crypto map outside_map 65535 ipsec-isakmp dynamic mydynamic
crypto map outside_map interface outside
By default, remote access VPN using IPsec VPN clients use XAUTH for user
authentication. Administrators can verify whether the VPN client is using
XAUTH by using the show running-config all tunnel-group <tg_name>
ipsec-attributes | include xauth command and verifying that ikev1
user-authentication xauth is present. The following example shows a
Cisco ASA Software appliance with a tunnel-group named RAVPN and with XAUTH
configured:
ciscoasa# show running-config all tunnel-group RAVPN ipsec-attributes | include xauth
[...]
ikev1 user-authentication xauth
Note: Remote access VPN using an IPsec client is not configured by default;
however, when configured, the XAUTH feature will be enabled.
Determining the Running Software Release
To determine whether a vulnerable release of Cisco ASA Software is running
on an appliance, administrators can use the show version command. The
following example shows the results of the show version command on an
appliance running Cisco ASA Software Release 9.2(1):
ciscoasa# show version | include Version
Cisco Adaptive Security Appliance Software Version 9.2(1)
Device Manager Version 7.4(1)
Customers who use Cisco Adaptive Security Device Manager (ASDM) to manage
devices can locate the software release in the table that appears in the
login window or the upper-left corner of the Cisco ASDM window.
Products Confirmed Not Vulnerable
No other Cisco products are currently known to be affected by this
vulnerability.
Workarounds
There are no workarounds that address this vulnerability
Fixed Software
Cisco has released free software updates that address the vulnerability
described in this advisory. Customers may only install and expect support
for software versions and feature sets for which they have purchased a
license. By installing, downloading, accessing, or otherwise using such
software upgrades, customers agree to follow the terms of the Cisco
software license:
http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html
Additionally, customers may only download software for which they have a
valid license, procured from Cisco directly, or through a Cisco authorized
reseller or partner. In most cases this will be a maintenance upgrade to
software that was previously purchased. Free security software updates do
not entitle customers to a new software license, additional software
feature sets, or major revision upgrades.
When considering software upgrades, customers are advised to regularly
consult the advisories for Cisco products, which are available from the
Cisco Security Advisories and Alerts page, to determine exposure and a
complete upgrade solution.
In all cases, customers should ensure that the devices to be upgraded
contain sufficient memory and confirm that current hardware and software
configurations will continue to be supported properly by the new release.
If the information is not clear, customers are advised to contact the Cisco
Technical Assistance Center (TAC) or their contracted maintenance
providers.
Customers Without Service Contracts
Customers who purchase directly from Cisco but do not hold a Cisco service
contract and customers who make purchases through third-party vendors but
are unsuccessful in obtaining fixed software through their point of sale
should obtain upgrades by contacting the Cisco TAC:
http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.html
Customers should have the product serial number available and be prepared
to provide the URL of this advisory as evidence of entitlement to a free
upgrade.
Fixed Releases
In the following table, the left column lists major releases of Cisco ASA
Software. The right column indicates whether a major release is affected by
the vulnerability described in this advisory and the first release that
includes the fix for this vulnerability.
Cisco ASA Software First Fixed Release
Major Release
Prior to 9.0^1 Affected, migrate to 9.1(7.7) or later
9.0^1 Affected, migrate to 9.1(7.7) or later
9.1 9.1(7.7) or later
9.2 9.2(4.11) or later
9.3^1 Affected, migrate to 9.4(4) or later
9.4 9.4(4) or later
9.5 9.5(3) or later
9.6 9.6(1.5) or later
9.7 Not affected
9.8 Not affected
^1 Cisco ASA Software releases prior to 9.1 and Cisco ASA Software Release
9.3 have reached end-of-software maintenance. Customers should migrate to a
supported release.
Note: It is possible that certain fixed software releases for this
vulnerability are affected by a bug described in Cisco Field Notice
FN-64291 where a security appliance may fail to pass traffic after 213 days
of uptime. Customers should review this notice before determining a course
of action for addressing the vulnerability described in this advisory. The
issue described in the Cisco Field Notice is not a security vulnerability.
Exploitation and Public Announcements
The Cisco Product Security Incident Response Team (PSIRT) is not aware of
any public announcements or malicious use of the vulnerability that is
described in this advisory.
Source
This vulnerability was found during the resolution of support cases.
Cisco Security Vulnerability Policy
To learn about Cisco security vulnerability disclosure policies and
publications, see the Security Vulnerability Policy. This document also
contains instructions for obtaining fixed software and receiving security
vulnerability information from Cisco.
Subscribe to Cisco Security Notifications
Subscribe
URL
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-xauth
Revision History
Version Description Section Status Date
1.0 Initial public release. Final 2017-April-19
Legal Disclaimer
THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND
OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT
OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES
THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.
A standalone copy or paraphrase of the text of this document that omits the
distribution URL is an uncontrolled copy and may lack important information
or contain factual errors. The information in this document is intended for
end users of Cisco products.
Cisco Security Vulnerability Policy
To learn about Cisco security vulnerability disclosure policies and
publications, see the Security Vulnerability Policy. This document also
contains instructions for obtaining fixed software and receiving security
vulnerability information from Cisco.
===
Cisco Security Advisory
Cisco ASA Software SSL/TLS Denial of Service Vulnerability
High
Advisory ID:
cisco-sa-20170419-asa-tls
First Published:
2017 April 19 16:00 GMT
Version 1.0:
Final
Workarounds:
No workarounds available
Cisco Bug IDs:
CSCuv48243
CVE-2017-6608
CWE-399
CVSS Score:
Base 8.6, Temporal 8.6
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:X/RL:X/RC:X
CVE-2017-6608
CWE-399
Summary
A vulnerability in the Secure Sockets Layer (SSL) and Transport Layer
Security (TLS) code of Cisco ASA Software could allow an unauthenticated,
remote attacker to cause a reload of the affected system.
The vulnerability is due to improper parsing of crafted SSL or TLS packets.
An attacker could exploit this vulnerability by sending a crafted packet to
the affected system.
Note: Only traffic directed to the affected system can be used to exploit
this vulnerability. This vulnerability affects systems configured in routed
and transparent firewall mode and in single or multiple context mode. This
vulnerability can be triggered by IPv4 and IPv6 traffic. A valid SSL or TLS
session is needed to exploit this vulnerability.
Cisco has released software updates that address this vulnerability. There
are no workarounds that address this vulnerability.
This advisory is available at the following link:
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/
cisco-sa-20170419-asa-tls
Affected Products
Vulnerable Products
This vulnerability affects Cisco ASA Software running on the following
products:
Cisco ASA 1000V Cloud Firewall
Cisco ASA 5500 Series Adaptive Security Appliances
Cisco ASA 5500-X Series Next-Generation Firewalls
Cisco ASA Services Module for Cisco Catalyst 6500 Series Switches and
Cisco 7600 Series Routers
Cisco Adaptive Security Virtual Appliance (ASAv)
Cisco Firepower 9300 ASA Security Module
Cisco ISA 3000 Industrial Security Appliance
Refer to the Fixed Software section of this security advisory for more
information about affected releases.
Cisco ASA Software is affected if it processes SSL or TLS packets. There
are multiple features that, when enabled, cause Cisco ASA Software to
process this type of packet. These features include, but are not limited
to, the following:
AnyConnect and Clientless SSL VPN
HTTP server used for the management interface
To verify whether an appliance running Cisco ASA Software could process SSL
or TLS packets, use the show asp table socket | include SSL command and
verify that it returns output. The following example shows a Cisco ASA
appliance configured with Clientless SSL VPN and with the HTTP server
enabled on the management interface and configured to listen on port 8443.
BSNS-ASA5505-4# show asp table socket | include SSL
SSL 0005aa68 LISTEN x.x.x.x:443 0.0.0.0:*
SSL 002d9e38 LISTEN x.x.x.x:8443 0.0.0.0:*
Determining the Running Software Release
To determine whether a vulnerable release of Cisco ASA Software is running
on an appliance, administrators can use the show version command. The
following example shows the results of the show version command on an
appliance running Cisco ASA Software Release 9.2(1):
ciscoasa# show version | include Version
Cisco Adaptive Security Appliance Software Version 9.2(1)
Device Manager Version 7.4(1)
Customers who use Cisco Adaptive Security Device Manager (ASDM) to manage
devices can locate the software release in the table that appears in the
login window or the upper-left corner of the Cisco ASDM window.
Products Confirmed Not Vulnerable
No other Cisco products are currently known to be affected by this
vulnerability.
Workarounds
There are no workarounds that address this vulnerability.
Fixed Software
Cisco has released free software updates that address the vulnerability
described in this advisory. Customers may only install and expect support
for software versions and feature sets for which they have purchased a
license. By installing, downloading, accessing, or otherwise using such
software upgrades, customers agree to follow the terms of the Cisco
software license:
http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html
Additionally, customers may only download software for which they have a
valid license, procured from Cisco directly, or through a Cisco authorized
reseller or partner. In most cases this will be a maintenance upgrade to
software that was previously purchased. Free security software updates do
not entitle customers to a new software license, additional software
feature sets, or major revision upgrades.
When considering software upgrades, customers are advised to regularly
consult the advisories for Cisco products, which are available from the
Cisco Security Advisories and Alerts page, to determine exposure and a
complete upgrade solution.
In all cases, customers should ensure that the devices to be upgraded
contain sufficient memory and confirm that current hardware and software
configurations will continue to be supported properly by the new release.
If the information is not clear, customers are advised to contact the Cisco
Technical Assistance Center (TAC) or their contracted maintenance
providers.
Customers Without Service Contracts
Customers who purchase directly from Cisco but do not hold a Cisco service
contract and customers who make purchases through third-party vendors but
are unsuccessful in obtaining fixed software through their point of sale
should obtain upgrades by contacting the Cisco TAC:
http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.html
Customers should have the product serial number available and be prepared
to provide the URL of this advisory as evidence of entitlement to a free
upgrade.
Fixed Releases
In the following table, the left column lists major releases of Cisco ASA
Software. The right column indicates whether a major release is affected by
the vulnerability described in this advisory and the first release that
includes the fix for this vulnerability.
Cisco ASA First Fixed Release
Software
Major Release
Prior to 9.0^1 Affected, migrate to 8.4(7.31) or 9.1(7) or
later
9.0^1 9.0(4.39) or later
9.1 9.1(7) or later
9.2 9.2(4.6) or later
9.3^1 9.3(3.8) or later
9.4 9.4(2) or later
9.5 9.5(2) or later
9.6 Not affected
9.7 Not affected
9.8 Not affected
^1 Cisco ASA Software releases prior to 9.1 and Cisco ASA Software Release
9.3 have reached end-of-software maintenance. Customers should migrate to a
supported release.
Note: It is possible that certain fixed software releases for this
vulnerability are affected by a bug described in Cisco Field Notice
FN-64291 where a security appliance may fail to pass traffic after 213 days
of uptime. Customers should review this notice before determining a course
of action for addressing the vulnerability described in this advisory. The
issue described in the Cisco Field Notice is not a security vulnerability.
Exploitation and Public Announcements
The Cisco Product Security Incident Response Team (PSIRT) is not aware of
any public announcements or malicious use of the vulnerability that is
described in this advisory.
Source
This vulnerability was found during internal testing.
Cisco Security Vulnerability Policy
To learn about Cisco security vulnerability disclosure policies and
publications, see the Security Vulnerability Policy. This document also
contains instructions for obtaining fixed software and receiving security
vulnerability information from Cisco.
Subscribe to Cisco Security Notifications
Subscribe
URL
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-tls
Revision History
Version Description Section Status Date
1.0 Initial public release. Final 2017-April-19
Legal Disclaimer
THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND
OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT
OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES
THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.
A standalone copy or paraphrase of the text of this document that omits the
distribution URL is an uncontrolled copy and may lack important information
or contain factual errors. The information in this document is intended for
end users of Cisco products.
Cisco Security Vulnerability Policy
To learn about Cisco security vulnerability disclosure policies and
publications, see the Security Vulnerability Policy. This document also
contains instructions for obtaining fixed software and receiving security
vulnerability information from Cisco.
===
Cisco Security Advisory
Cisco ASA Software and Cisco FTD Software TCP Normalizer Denial of Service
Vulnerability
Medium
Advisory ID:
cisco-sa-20170419-asa-norm
First Published:
2017 April 19 16:00 GMT
Version 1.0:
Final
Workarounds:
No workarounds available
Cisco Bug IDs:
CSCvb46321
CVE-2017-3793
CWE-399
CVSS Score:
Base 4.0, Temporal 4.0
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:L/E:X/RL:X/RC:X
CVE-2017-3793
CWE-399
Summary
A vulnerability in the TCP normalizer of Cisco Adaptive Security Appliance
(ASA) Software and Cisco Firepower Threat Defense (FTD) Software could
allow an unauthenticated, remote attacker to cause Cisco ASA and FTD to
drop any further incoming traffic on all interfaces, resulting in a denial
of service (DoS) condition.
The vulnerability is due to improper limitation of the global out-of-order
TCP queue for specific block sizes. An attacker could exploit this
vulnerability by sending a large number of unique permitted TCP connections
with out-of-order segments. An exploit could allow the attacker to exhaust
available blocks in the global out-of-order TCP queue, causing the dropping
of any further incoming traffic on all interfaces and resulting in a DoS
condition.
There are no workarounds that address this vulnerability.
This advisory is available at the following link:
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-norm
Affected Products
Vulnerable Products
This vulnerability affects Cisco products running Cisco ASA Software and
Cisco products running Cisco FTD Software. For information about affected
software releases, consult the Cisco bug ID(s) at the top of this advisory.
Products Confirmed Not Vulnerable
No other Cisco products are currently known to be affected by this
vulnerability.
Workarounds
There are no workarounds that address this vulnerability.
Fixed Software
For information about fixed software releases, consult the Cisco bug ID(s)
at the top of this advisory.
When considering software upgrades, customers are advised to consult the
advisories for Cisco products, which are available from the Cisco Security
Advisories and Alerts page, to determine exposure and a complete upgrade
solution.
In all cases, customers should ensure that the devices to be upgraded
contain sufficient memory and confirm that current hardware and software
configurations will continue to be supported properly by the new release.
If the information is not clear, customers are advised to contact the Cisco
Technical Assistance Center (TAC) or their contracted maintenance
providers.
Exploitation and Public Announcements
The Cisco Product Security Incident Response Team (PSIRT) is not aware of
any public announcements or malicious use of the vulnerability that is
described in this advisory.
Source
This vulnerability was found during internal testing.
Cisco Security Vulnerability Policy
To learn about Cisco security vulnerability disclosure policies and
publications, see the Security Vulnerability Policy. This document also
contains instructions for obtaining fixed software and receiving security
vulnerability information from Cisco.
Subscribe to Cisco Security Notifications
Subscribe
URL
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-norm
Revision History
Version Description Section Status Date
1.0 Initial public release. Final 2017-April-19
Legal Disclaimer
THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND
OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT
OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES
THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.
A standalone copy or paraphrase of the text of this document that omits the
distribution URL is an uncontrolled copy and may lack important information
or contain factual errors. The information in this document is intended for
end users of Cisco products.
Cisco Security Vulnerability Policy
To learn about Cisco security vulnerability disclosure policies and
publications, see the Security Vulnerability Policy. This document also
contains instructions for obtaining fixed software and receiving security
vulnerability information from Cisco.
===
Cisco Security Advisory
Cisco ASA Software IPsec Denial of Service Vulnerability
High
Advisory ID:
cisco-sa-20170419-asa-ipsec
First Published:
2017 April 19 16:00 GMT
Version 1.0:
Final
Workarounds:
No workarounds available
Cisco Bug IDs:
CSCun16158
CVE-2017-6609
CWE-399
CVSS Score:
Base 7.7, Temporal 7.7
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H/E:X/RL:X/RC:X
CVE-2017-6609
CWE-399
Summary
A vulnerability in the IPsec code of Cisco ASA Software could allow an
authenticated, remote attacker to cause a reload of the affected system.
The vulnerability is due to improper parsing of malformed IPsec packets. An
attacker could exploit this vulnerability by sending malformed IPsec
packets to the affected system.
Note: Only traffic directed to the affected system can be used to exploit
this vulnerability. This vulnerability affects systems configured in routed
firewall mode only and in single or multiple context mode. This
vulnerability can be triggered by IPv4 and IPv6 traffic. An attacker needs
to establish a valid IPsec tunnel before exploiting this vulnerability.
Cisco has released software updates that address this vulnerability. There
are no workarounds that address this vulnerability.
This advisory is available at the following link:
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-ipsec
Affected Products
Vulnerable Products
This vulnerability affects Cisco ASA Software running on the following
products:
Cisco ASA 1000V Cloud Firewall
Cisco ASA 5500 Series Adaptive Security Appliances
Cisco ASA 5500-X Series Next-Generation Firewalls
Cisco ASA Services Module for Cisco Catalyst 6500 Series Switches and
Cisco 7600 Series Routers
Cisco Adaptive Security Virtual Appliance (ASAv)
Cisco Firepower 9300 ASA Security Module
Cisco ISA 3000 Industrial Security Appliance
Refer to the Fixed Software section of this security advisory for more
information about affected releases.
Cisco ASA Software is affected by this vulnerability if the system is
configured to terminate IPsec VPN connections. This includes the following:
LAN-to-LAN IPsec VPN
Remote access VPN using the IPsec VPN client
Layer 2 Tunneling Protocol (L2TP)-over-IPsec VPN connections
Internet Key Exchange Version 2 (IKEv2) AnyConnect
Cisco ASA Software is not affected by this vulnerability if the system is
configured to terminate only the following VPN connections:
Clientless SSL
AnyConnect SSL
To determine whether an appliance running Cisco ASA Software is configured
to terminate IPsec VPN connections, a crypto map must be configured for at
least one interface. Administrators should use the show running-config
crypto map | include interface command and verify that it returns output.
The following example shows a crypto map named outside_map configured on
the outside interface:
ciscoasa# show running-config crypto map | include interface
crypto map outside_map interface outside
Note: IPsec VPN is not configured by default.
Determining the Running Software Release
To determine whether a vulnerable release of Cisco ASA Software is running
on an appliance, administrators can use the show version command. The
following example shows the results of the show version command on an
appliance running Cisco ASA Software Release 9.2(1):
ciscoasa# show version | include Version
Cisco Adaptive Security Appliance Software Version 9.2(1)
Device Manager Version 7.4(1)
Customers who use Cisco Adaptive Security Device Manager (ASDM) to manage
devices can locate the software release in the table that appears in the
login window or the upper-left corner of the Cisco ASDM window.
Products Confirmed Not Vulnerable
No other Cisco products are currently known to be affected by this
vulnerability.
Cisco has confirmed that this vulnerability does not affect Cisco Firepower
Threat Defense Software.
Workarounds
There are no workarounds that address this vulnerability.
Fixed Software
Cisco has released free software updates that address the vulnerability
described in this advisory. Customers may only install and expect support
for software versions and feature sets for which they have purchased a
license. By installing, downloading, accessing, or otherwise using such
software upgrades, customers agree to follow the terms of the Cisco
software license:
http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html
Additionally, customers may only download software for which they have a
valid license, procured from Cisco directly, or through a Cisco authorized
reseller or partner. In most cases this will be a maintenance upgrade to
software that was previously purchased. Free security software updates do
not entitle customers to a new software license, additional software
feature sets, or major revision upgrades.
When considering software upgrades, customers are advised to regularly
consult the advisories for Cisco products, which are available from the
Cisco Security Advisories and Alerts page, to determine exposure and a
complete upgrade solution.
In all cases, customers should ensure that the devices to be upgraded
contain sufficient memory and confirm that current hardware and software
configurations will continue to be supported properly by the new release.
If the information is not clear, customers are advised to contact the Cisco
Technical Assistance Center (TAC) or their contracted maintenance
providers.
Customers Without Service Contracts
Customers who purchase directly from Cisco but do not hold a Cisco service
contract and customers who make purchases through third-party vendors but
are unsuccessful in obtaining fixed software through their point of sale
should obtain upgrades by contacting the Cisco TAC:
http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.html
Customers should have the product serial number available and be prepared
to provide the URL of this advisory as evidence of entitlement to a free
upgrade.
Fixed Releases
In the following table, the left column lists major releases of Cisco ASA
Software. The right column indicates whether a major release is affected by
the vulnerability described in this advisory and the first release that
includes the fix for this vulnerability.
Cisco ASA Software First Fixed Release
Major Release
Prior to 9.0^1 Affected, migrate to 9.1(7.8) or later
9.0^1 Affected, migrate to 9.1(7.8) or later
9.1 9.1(7.8) or later
9.2 9.2(4.15) or later
9.3^1 Affected, migrate to 9.4(4) or later
9.4 9.4(4) or later
9.5 9.5(3.2) or later
9.6 9.6(2) or later
9.7 Not affected
9.8 Not affected
^1 Cisco ASA Software releases prior to 9.1 and Cisco ASA Software Release
9.3 have reached end-of-software maintenance. Customers should migrate to a
supported release.
Note: It is possible that certain fixed software releases for this
vulnerability are affected by a bug described in Cisco Field Notice
FN-64291 where a security appliance may fail to pass traffic after 213 days
of uptime. Customers should review this notice before determining a course
of action for addressing the vulnerability described in this advisory. The
issue described in the Cisco Field Notice is not a security vulnerability.
Exploitation and Public Announcements
The Cisco Product Security Incident Response Team (PSIRT) is not aware of
any public announcements or malicious use of the vulnerability that is
described in this advisory.
Source
This vulnerability was found during internal testing.
Cisco Security Vulnerability Policy
To learn about Cisco security vulnerability disclosure policies and
publications, see the Security Vulnerability Policy. This document also
contains instructions for obtaining fixed software and receiving security
vulnerability information from Cisco.
Subscribe to Cisco Security Notifications
Subscribe
URL
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-asa-ipsec
Revision History
Version Description Section Status Date
1.0 Initial public release. Final 2017-April-19
Legal Disclaimer
THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND
OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT
OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES
THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.
A standalone copy or paraphrase of the text of this document that omits the
distribution URL is an uncontrolled copy and may lack important information
or contain factual errors. The information in this document is intended for
end users of Cisco products.
Cisco Security Vulnerability Policy
To learn about Cisco security vulnerability disclosure policies and
publications, see the Security Vulnerability Policy. This document also
contains instructions for obtaining fixed software and receiving security
vulnerability information from Cisco.
- --------------------------END INCLUDED TEXT--------------------
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