-----BEGIN PGP SIGNED MESSAGE-----
AUSCERT External Security Bulletin Redistribution
Cisco IOS and IOS XE Software IKEv1 State Machine Denial of
23 December 2015
AusCERT Security Bulletin Summary
Product: Cisco IOS and IOS XE
Publisher: Cisco Systems
Operating System: Cisco
Impact/Access: Denial of Service -- Remote/Unauthenticated
CVE Names: CVE-2015-6429
- --------------------------BEGIN INCLUDED TEXT--------------------
Cisco Security Advisory
Cisco IOS and IOS XE Software IKEv1 State Machine Denial of Service
2015 December 18 08:00 GMT
Base - 5.0
No workarounds available
Cisco Bug IDs:
A vulnerability in the Internet Key Exchange (IKEv1) state machine of
Cisco IOS and Cisco IOS XE Software could allow an unauthenticated,
remote attacker to tear down valid IPsec connections, resulting in a
partial denial of service (DoS) condition.
The vulnerability is due to insufficient condition checks in the IKEv1
state machine. An attacker could exploit this vulnerability by sending
a spoofed, specific IKEv1 packet to an endpoint of an IPsec tunnel. A
successful exploit could allow the attacker to tear down IPsec tunnels
that terminate on the endpoint, causing a partial DoS condition.
Cisco has released software updates that address this
vulnerability. There are no workarounds that mitigate this vulnerability.
This advisory is available at the following link:
Cisco IOS and Cisco IOS XE Software Releases prior to 15.5(2)S2
(3.15.2S), 15.5(2)T2, 15.5(3)M1, 15.5(3)S1 (3.16.1S), 15.6(1)S (3.17.1S),
and 15.6(1)T are vulnerable.
Products Confirmed Not Vulnerable
No other Cisco products are currently known to be affected by this
There are no workarounds that mitigate this vulnerability.
When considering software upgrades, customers are advised to
consult the Cisco Security Advisories and Responses archive at
http://www.cisco.com/go/psirt and review subsequent advisories to
determine exposure and a complete upgrade solution.
In all cases, customers should ensure that the devices to upgrade
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
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.
Version Description Section Status Date
1.0 Initial public release. Final 2015-December-18
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.
- --------------------------END INCLUDED TEXT--------------------
You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to email@example.com
and we will forward your request to the appropriate person.
NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members. As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.
NOTE: This is only the original release of the security bulletin. It may
not be updated when updates to the original are made. If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.
Contact information for the authors of the original document is included
in the Security Bulletin above. If you have any questions or need further
information, please contact them directly.
Previous advisories and external security bulletins can be retrieved from:
Australian Computer Emergency Response Team
The University of Queensland
Internet Email: firstname.lastname@example.org
Facsimile: (07) 3365 7031
Telephone: (07) 3365 4417 (International: +61 7 3365 4417)
AusCERT personnel answer during Queensland business hours
which are GMT+10:00 (AEST).
On call after hours for member emergencies only.
-----BEGIN PGP SIGNATURE-----
-----END PGP SIGNATURE-----