CyberSecBulletin
CVE-2025-38212NVD status: Modified

Linux: Use After Free

Published Updated By the CyberSecBulletin desk

CVE-2025-38212 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 5f1e1573bf103303944fd7225559de5d8297539c, b968ba8bfd9f90914957bbbd815413bf6a98eca7, 74bc813d11c30e28fc5261dc877cca662ccfac68 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 0.2% 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 5f1e1573bf103303944fd7225559de5d8297539c or b968ba8bfd9f90914957bbbd815413bf6a98eca7 or 74bc813d11c30e28fc5261dc877cca662ccfac68 or 78297d53d3878d43c1d627d20cd09f611fa4b91d, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.4.295 or 5.10.239 or 5.15.186 or 6.1.142, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxb34a6b1da371ed8af1221459a18c67970f7e3d53 up to, but not including, 5f1e1573bf103303944fd7225559de5d8297539c; b34a6b1da371ed8af1221459a18c67970f7e3d53 up to, but not including, b968ba8bfd9f90914957bbbd815413bf6a98eca7; b34a6b1da371ed8af1221459a18c67970f7e3d53 up to, but not including, 74bc813d11c30e28fc5261dc877cca662ccfac68; b34a6b1da371ed8af1221459a18c67970f7e3d53 up to, but not including, 78297d53d3878d43c1d627d20cd09f611fa4b91d; b34a6b1da371ed8af1221459a18c67970f7e3d53 up to, but not including, 5180561afff8e0f029073c8c8117c95c6512d1f9; b34a6b1da371ed8af1221459a18c67970f7e3d53 up to, but not including, 68c173ea138b66d7dd1fd980c9bc578a18e11884; b34a6b1da371ed8af1221459a18c67970f7e3d53 up to, but not including, b0b6bf90ce2699a574b3683e22c44d0dcdd7a057; b34a6b1da371ed8af1221459a18c67970f7e3d53 up to, but not including, d66adabe91803ef34a8b90613c81267b5ded1472; and 1 more ranges5f1e1573bf103303944fd7225559de5d8297539c, b968ba8bfd9f90914957bbbd815413bf6a98eca7, 74bc813d11c30e28fc5261dc877cca662ccfac68, 78297d53d3878d43c1d627d20cd09f611fa4b91d, 5180561afff8e0f029073c8c8117c95c6512d1f9, 68c173ea138b66d7dd1fd980c9bc578a18e11884
SiemensSIMATIC S7-1500 CPU 1518-4 PN/DP MFPV3.1.5 and laterNot stated
SiemensSIMATIC S7-1500 CPU 1518F-4 PN/DP MFPV3.1.5 and laterNot stated
SiemensSIPLUS S7-1500 CPU 1518-4 PN/DP MFPV3.1.5 and laterNot stated
LinuxLinux Kernel3.1 up to, but not including, 5.4.295; 5.5 up to, but not including, 5.10.239; 5.11 up to, but not including, 5.15.186; 5.16 up to, but not including, 6.1.142; 6.2 up to, but not including, 6.6.95; 6.7 up to, but not including, 6.12.35; 6.13 up to, but not including, 6.15.45.4.295, 5.10.239, 5.15.186, 6.1.142, 6.6.95, 6.12.35
DebianDebian Linux11.0Not stated

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
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighCNA
CVSS 3.17.8HighNVD

Official description

In the Linux kernel, the following vulnerability has been resolved: ipc: fix to protect IPCS lookups using RCU syzbot reported that it discovered a use-after-free vulnerability, [0] [0]: https://lore.kernel.org/all/[email protected]/ idr_for_each() is protected by rwsem, but this is not enough. If it is not protected by RCU read-critical region, when idr_for_each() calls radix_tree_node_free() through call_rcu() to free the radix_tree_node structure, the node will be freed immediately, and when reading the next node in radix_tree_for_each_slot(), the already freed memory may be read. Therefore, we need to add code to make sure that idr_for_each() is protected within the RCU read-critical region when we call it in shm_destroy_orphaned().

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

The underlying weakness: Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

More Use After Free vulnerabilities (CWE-416)

Timeline

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

References

Third-party and government advisories

Recent Use After Free vulnerabilities

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