CyberSecBulletin
CVE-2024-21849NVD status: Analyzed

BIG-IP: Return of Pointer Value Outside of Expected Range

CVE-2024-21849 is a high-severity return of pointer value outside of expected range vulnerability in BIG-IP from F5, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 16.1.4 as the first without the flaw, so updating BIG-IP to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.52% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update BIG-IP to 16.1.4 or a later version.
  2. Update Big-ip Advanced Web Application Firewall to 16.1.4 or a later version.
  3. Update Big-ip Application Security Manager to 16.1.4 or a later version.
  4. Read the advisory on my.f5.com for workarounds and exact fixed builds.
  5. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
F5BIG-IP16.1.0 up to, but not including, 16.1.416.1.4
F5Big-ip Advanced Web Application Firewall16.1.0 up to, but not including, 16.1.416.1.4
F5Big-ip Application Security Manager16.1.0 up to, but not including, 16.1.416.1.4

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighCNA (f5.com)
CVSS 3.17.5HighNVD

Official description

When an Advanced WAF/ASM security policy and a Websockets profile are configured on a virtual server, undisclosed traffic can cause the Traffic Management Microkernel (TMM) process to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Return of Pointer Value Outside of Expected Range

A function can return a pointer to memory that is outside of the buffer that the pointer is expected to reference.

More Return of Pointer Value Outside of Expected Range vulnerabilities (CWE-466)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in BIG-IP

All BIG-IP vulnerabilities

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