CyberSecBulletin
CVE-2026-46024NVD status: Modified

Linux: NULL Pointer Dereference

Published Updated By the CyberSecBulletin desk

CVE-2026-46024 is a high-severity NULL pointer dereference vulnerability in Linux, 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 versions 9ded62c302c0342efdb5eda3bf6e75720caad0df, f101271fcf55d7eacfefd610b51ec65f46ba8118, 4b2738b93edad661178340239de657d876b73d3d as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.49% 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 Linux to 9ded62c302c0342efdb5eda3bf6e75720caad0df or f101271fcf55d7eacfefd610b51ec65f46ba8118 or 4b2738b93edad661178340239de657d876b73d3d or 927e4bd5692f2a4901808822981fb2c8d4456548, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.15.209 or 6.1.175 or 6.6.140 or 6.12.86, whichever matches your release line, or a later version.
  3. 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
LinuxLinux4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc up to, but not including, 9ded62c302c0342efdb5eda3bf6e75720caad0df; 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc up to, but not including, f101271fcf55d7eacfefd610b51ec65f46ba8118; 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc up to, but not including, 4b2738b93edad661178340239de657d876b73d3d; 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc up to, but not including, 927e4bd5692f2a4901808822981fb2c8d4456548; 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc up to, but not including, 016bc663657366d386993f63eb31072eb45a2b77; 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc up to, but not including, 8f2be7285941a33a9f72579a23b96392f83c758e; 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc up to, but not including, 5199c125d25aeae8615c4fc31652cc0fe624338e; 2.6.349ded62c302c0342efdb5eda3bf6e75720caad0df, f101271fcf55d7eacfefd610b51ec65f46ba8118, 4b2738b93edad661178340239de657d876b73d3d, 927e4bd5692f2a4901808822981fb2c8d4456548, 016bc663657366d386993f63eb31072eb45a2b77, 8f2be7285941a33a9f72579a23b96392f83c758e
LinuxLinux Kernel2.6.34.1 up to, but not including, 5.15.209; 5.16 up to, but not including, 6.1.175; 6.2 up to, but not including, 6.6.140; 6.7 up to, but not including, 6.12.86; 6.13 up to, but not including, 6.18.27; 6.19 up to, but not including, 7.0.4; 2.6.345.15.209, 6.1.175, 6.6.140, 6.12.86, 6.18.27, 7.0.4

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 CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: libceph: Prevent potential null-ptr-deref in ceph_handle_auth_reply() If a message of type CEPH_MSG_AUTH_REPLY contains a zero value for both protocol and result, this is currently not treated as an error. In case of ac->negotiating == true and ac->protocol > 0, this leads to setting ac->protocol = 0 and ac->ops = NULL. Thereafter, the check for ac->protocol != protocol returns false, and init_protocol() is not called. Subsequently, ac->ops->handle_reply() is called, which leads to a null pointer dereference, because ac->ops is still NULL. This patch changes the check for ac->protocol != protocol to !ac->protocol, as this also includes the case when the protocol was set to zero in the message. This causes the message to be treated as containing a bad auth protocol.

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

Recent NULL Pointer Dereference vulnerabilities

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