Hash: SHA256

             AUSCERT External Security Bulletin Redistribution

                K43625118:TMM vulnerability CVE-2018-15317
                              12 August 2019


        AusCERT Security Bulletin Summary

Product:           F5 BIG-IP Products
Publisher:         F5 Networks
Operating System:  Network Appliance
Impact/Access:     Denial of Service -- Remote/Unauthenticated
Resolution:        Patch/Upgrade
CVE Names:         CVE-2018-15317  

Original Bulletin: 

Revision History:  August 12 2019: Vendor added information about more versions
                   May    29 2019: Updated with latest revision
                   May     9 2019: Updated version numbers in product table
                   May     8 2019: Updated hotfix info for BIG-IP products
                   April  16 2019: Initial Release

- --------------------------BEGIN INCLUDED TEXT--------------------

K43625118:TMM vulnerability CVE-2018-15317

Security Advisory

Original Publication Date: 31 Oct, 2018

Latest   Publication Date: 10 Aug, 2019

Security Advisory Description

In BIG-IP 14.0.0-, 13.0.0-, 12.1.0-, and
11.2.1-, an attacker sending specially crafted SSL records to a SSL
Virtual Server will cause corruption in the SSL data structures leading to
intermittent decrypt BAD_RECORD_MAC errors. Clients will be unable to access
the application load balanced by a virtual server with an SSL profile until tmm
is restarted. (CVE-2018-15317)


The vulnerability allows remote attackers to cause a denial of service (DoS) on
the BIG-IP system.

Security Advisory Status

F5 Product Development has assigned ID 715923 (BIG-IP) to this vulnerability.
Additionally, BIG-IP iHealth may list Heuristic H43625118 on the Diagnostics >
Identified > High page.

To determine if your product and version have been evaluated for this
vulnerability, refer to the Applies to (see versions) box. To determine if your
release is known to be vulnerable, the components or features that are affected
by the vulnerability, and for information about releases or hotfixes that
address the vulnerability, refer to the following table. For more information
about security advisory versioning, refer to K51812227: Understanding Security
Advisory versioning.

|                  |      |Versions  |Fixes     |           |CVSSv3|Vulnerable|
|Product           |Branch|known to  |introduced|Severity   |score^|component |
|                  |      |be        |in        |           |1     |or feature|
|                  |      |vulnerable|          |           |      |          |
|                  |14.x  |14.0.0 -  |14.1.0    |           |      |          |
|                  |      |  |  |           |      |          |
|                  +------+----------+----------+           |      |          |
|BIG-IP (LTM, AAM, |13.x  |13.0.0 -  |13.1.3    |           |      |          |
|AFM, Analytics,   |      |13.1.1    |          |           |      |          |
|APM, ASM, DNS,    +------+----------+----------+           |      |TMM (SSL  |
|Edge Gateway, FPS,|12.x  |12.1.0 -  |12.1.5    |High       |7.5   |virtual   |
|GTM, Link         |      |12.1.4    |          |           |      |servers)  |
|Controller, PEM,  +------+----------+----------+           |      |          |
|WebAccelerator)   |      |11.6.1 -  |          |           |      |          |
|                  |      |  |          |           |      |          |
|                  |11.x  |11.5.1 -  |  |           |      |          |
|                  |      |11.5.9    |          |           |      |          |
|                  |      |11.2.1    |          |           |      |          |
|                  |      |          |Not       |Not        |      |          |
|Enterprise Manager|3.x   |None      |applicable|vulnerable^|None  |None      |
|                  |      |          |          |2          |      |          |
|                  |5.x   |None      |Not       |           |      |          |
|BIG-IQ Centralized|      |          |applicable|Not        |      |          |
|Management        +------+----------+----------+vulnerable^|None  |None      |
|                  |4.x   |None      |Not       |2          |      |          |
|                  |      |          |applicable|           |      |          |
|BIG-IQ Cloud and  |      |          |Not       |Not        |      |          |
|Orchestration     |1.x   |None      |applicable|vulnerable^|None  |None      |
|                  |      |          |          |2          |      |          |
|                  |      |          |Not       |Not        |      |          |
|F5 iWorkflow      |2.x   |None      |applicable|vulnerable^|None  |None      |
|                  |      |          |          |2          |      |          |
|                  |5.x   |None      |Not       |           |      |          |
|                  |      |          |applicable|Not        |      |          |
|Traffix SDC       +------+----------+----------+vulnerable |None  |None      |
|                  |4.x   |None      |Not       |           |      |          |
|                  |      |          |applicable|           |      |          |

^1The CVSSv3 score link takes you to a resource outside of AskF5, and it is
possible that the document may be removed without our knowledge.

^2The specified products contain the affected code. However, F5 identifies the
vulnerability status as Not vulnerable because the attacker cannot exploit the
code in default, standard, or recommended configurations.

Security Advisory Recommended Actions

If you are running a version listed in the Versions known to be vulnerable
column, you can eliminate this vulnerability by upgrading to a version listed
in the Fixes introduced in column. If the table lists only an older version
than what you are currently running, or does not list a non-vulnerable version,
then no upgrade candidate currently exists.


If clients are unable to access the application loadbalanced by a virtual
server with an SSL profile due to BAD_RECORD_MAC errors, you can restart the
Traffic Management Microkernel (TMM), or if the affected device is in a device
group you can fail over to the next available device and restart TMM on the
affected device. To do so, perform one of the following procedures:

  o Restarting TMM
  o Failing over to the next available device in the device group

Restarting TMM

Impact of action: This procedure requires you to restart the TMM, which
interrupts traffic processing on the BIG-IP system. If you are using a self-IP
address to connect to the CLI, you will be disconnected.

 1. Log in to the TMOS Shell (tmsh) by typing the following command:


 2. Restart TMM by typing the following command:

    restart /sys service tmm

Failing over to the next available device in the device group

Impact of action: Traffic is briefly interrupted while a peer device takes over
the active role. If the upstream switch or router cannot quickly update either
the Content Addressable Memory (CAM) table or Address Resolution Protocol (ARP)
for the new MAC address, service may be disrupted. The F5 MAC masquerade
feature can help with this condition. For more information about MAC
Masquerade, refer to K13502: Configuring MAC masquerade (11.x - 14.x).

 1. Log in to the Configuration utility of the affected device.
 2. Verify that an available peer device is the traffic group's Next Active
    Device by navigating to Device Management > Traffic Groups.
 3. Navigate to Device Management > Devices and select the local system
    designated with Self.
 4. Click Force to Standby.

    The new BIG-IP system should change to active mode.

 5. Restart TMM on the affected device that is now in the standby role by
    performing the previous Restarting TMM procedure.

- --------------------------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 auscert@auscert.org.au
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
Qld 4072

Internet Email: auscert@auscert.org.au
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.
Comment: http://www.auscert.org.au/render.html?it=1967