CVE-2016-9256: Race Condition

Published May 9, 2017
·
Updated

In F5 BIG-IP 12.1.0 through 12.1.2, permissions enforced by iControl can lag behind the actual permissions assigned to a user if the rolemap is not reloaded between the time the permissions are changed and the time of the user's next request. This is a race condition that occurs rarely in normal usage; the typical period in which this is possible is limited to at most a few seconds after the permission change.

Affected Software

40 affected components
F5 Big-ip Local Traffic Manager=12.0.0
F5 Big-ip Local Traffic Manager=12.1.0
F5 Big-ip Local Traffic Manager=12.1.1
F5 Big-ip Local Traffic Manager=12.1.2
F5 Big-ip Application Acceleration Manager=12.0.0
F5 Big-ip Application Acceleration Manager=12.1.0
F5 Big-ip Application Acceleration Manager=12.1.1
F5 Big-ip Application Acceleration Manager=12.1.2
F5 BIG-IP Advanced Firewall Manager=12.0.0
F5 BIG-IP Advanced Firewall Manager=12.1.0
F5 BIG-IP Advanced Firewall Manager=12.1.1
F5 BIG-IP Advanced Firewall Manager=12.1.2
F5 BIG-IP Analytics=12.0.0
F5 BIG-IP Analytics=12.1.0
F5 BIG-IP Analytics=12.1.1
F5 BIG-IP Analytics=12.1.2
F5 BIG-IP Access Policy Manager=12.0.0
F5 BIG-IP Access Policy Manager=12.1.0
F5 BIG-IP Access Policy Manager=12.1.1
F5 BIG-IP Access Policy Manager=12.1.2
F5 BIG-IP Application Security Manager=12.0.0
F5 BIG-IP Application Security Manager=12.1.0
F5 BIG-IP Application Security Manager=12.1.1
F5 BIG-IP Application Security Manager=12.1.2
F5 Big-ip Domain Name System=12.0.0
F5 Big-ip Domain Name System=12.1.0
F5 Big-ip Domain Name System=12.1.1
F5 Big-ip Domain Name System=12.1.2
F5 Big-ip Link Controller=12.0.0
F5 Big-ip Link Controller=12.1.0
F5 Big-ip Link Controller=12.1.1
F5 Big-ip Link Controller=12.1.2
F5 Big-ip Policy Enforcement Manager=12.0.0
F5 Big-ip Policy Enforcement Manager=12.1.0
F5 Big-ip Policy Enforcement Manager=12.1.1
F5 Big-ip Policy Enforcement Manager=12.1.2
F5 Big-ip Websafe=12.0.0
F5 Big-ip Websafe=12.1.0
F5 Big-ip Websafe=12.1.1
F5 Big-ip Websafe=12.1.2

Event History

May 9, 2017
CVE Published
via MITRE·03:00 PM
Data Sourced
via MITRE·03:00 PM
DescriptionWeakness

Frequently Asked Questions

1

What is the severity of CVE-2016-9256?

The severity of CVE-2016-9256 is classified as high due to the potential for unauthorized access to user permissions.

2

How do I fix CVE-2016-9256?

To fix CVE-2016-9256, ensure you reload the role map in the iControl application immediately after changing user permissions.

3

Which F5 BIG-IP versions are affected by CVE-2016-9256?

Affected F5 BIG-IP versions include 12.1.0 through 12.1.2 and version 12.0.0 for certain components.

4

What causes CVE-2016-9256?

CVE-2016-9256 is caused by a race condition that arises when user permissions are changed but the role map is not reloaded before the next user request.

5

Is CVE-2016-9256 exploitable by attackers?

Yes, CVE-2016-9256 is exploitable, potentially allowing attackers to gain unauthorized access to system resources.

Contact

SecAlerts Pty Ltd.
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Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
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