CyberSecBulletin
CVE-2024-24989NVD status: Modified

NGINX Plus: NULL Pointer Dereference

CVE-2024-24989 is a high-severity NULL pointer dereference vulnerability in NGINX Plus 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 R31 P1 as the first without the flaw, so updating NGINX Plus to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.06% chance of exploitation within 30 days, higher than 65% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update NGINX Plus to R31 P1 or a later version.
  2. Update NGINX Open Source to 1.25.4 or a later version.
  3. Read the advisory on my.f5.com for workarounds and exact fixed builds.
  4. 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
F5NGINX PlusR31 up to, but not including, R31 P1R31 P1
F5NGINX Open Source1.25.3 up to, but not including, 1.25.41.25.4

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 NGINX Plus or NGINX OSS are configured to use the HTTP/3 QUIC module, undisclosed requests can cause NGINX worker processes to terminate. Note: The HTTP/3 QUIC module is not enabled by default and is considered experimental. For more information, refer to Support for QUIC and HTTP/3 https://nginx.org/en/docs/quic.html . 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: NULL Pointer Dereference

The product dereferences a pointer that it expects to be valid but is NULL.

How developers prevent this class of flaw

  • For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished.
  • Select a programming language that is not susceptible to these issues.
  • Check the results of all functions that return a value and verify that the value is non-null before acting upon it.

More NULL Pointer Dereference vulnerabilities (CWE-476)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in NGINX Plus

All NGINX Plus vulnerabilities

Recent NULL Pointer Dereference vulnerabilities

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