CVE intelligence and bounded remediation

CVE-2016-9256 — F5 Big-Ip Local Traffic Manager security vulnerability

High CVSS 7.5

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 role_map 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.

Severity
High
CVSS
7.5 (3.0)
Published
2017-05-09
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-362

Affected products

  • 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

Showing 6 representative product identities from 40 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Race condition, TOCTOU, and lifecycle synchronization

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Check exposure

  • Map concurrent actors, shared state, lock boundaries, signals, callbacks, retries, and check-then-use sequences in the affected path.
  • Determine whether untrusted users can influence timing, object names, filesystem state, or repeated state transitions.
  • Identify clustered and multi-process behavior that repository-local tests may not represent.

Remediate safely

  • Make the sensitive state transition atomic or protect it with a consistently ordered synchronization primitive.
  • Perform authorization and invariant checks on the same authoritative object and transaction used for the operation.
  • Use unique private resources, safe ownership transfer, and idempotent operations; add deterministic concurrency regression tests.

Authoritative sources

Complete CVE record and remediation plan

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