CyberSecBulletin
CVE-2025-38079NVD status: Modified

Linux: Double Free

Published Updated By the CyberSecBulletin desk

CVE-2025-38079 is a high-severity double 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 5bff312b59b3f2a54ff504e4f4e47272b64f3633, bf7bba75b91539e93615f560893a599c1e1c98bf, c3059d58f79fdfb2201249c2741514e34562b547 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 0.22% 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 5bff312b59b3f2a54ff504e4f4e47272b64f3633 or bf7bba75b91539e93615f560893a599c1e1c98bf or c3059d58f79fdfb2201249c2741514e34562b547 or f0f3d09f53534ea385d55ced408f2b67059b16e4, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.4.294 or 5.10.238 or 5.15.185 or 6.1.141, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxfe869cdb89c95d060c77eea20204d6c91f233b53 up to, but not including, 5bff312b59b3f2a54ff504e4f4e47272b64f3633; fe869cdb89c95d060c77eea20204d6c91f233b53 up to, but not including, bf7bba75b91539e93615f560893a599c1e1c98bf; fe869cdb89c95d060c77eea20204d6c91f233b53 up to, but not including, c3059d58f79fdfb2201249c2741514e34562b547; fe869cdb89c95d060c77eea20204d6c91f233b53 up to, but not including, f0f3d09f53534ea385d55ced408f2b67059b16e4; fe869cdb89c95d060c77eea20204d6c91f233b53 up to, but not including, 134daaba93193df9e988524b5cd2f52d15eb1993; fe869cdb89c95d060c77eea20204d6c91f233b53 up to, but not including, 2f45a8d64fb4ed4830a4b3273834ecd6ca504896; fe869cdb89c95d060c77eea20204d6c91f233b53 up to, but not including, 0346f4b742345d1c733c977f3a7aef5a6419a967; fe869cdb89c95d060c77eea20204d6c91f233b53 up to, but not including, b2df03ed4052e97126267e8c13ad4204ea6ba9b6; and 1 more ranges5bff312b59b3f2a54ff504e4f4e47272b64f3633, bf7bba75b91539e93615f560893a599c1e1c98bf, c3059d58f79fdfb2201249c2741514e34562b547, f0f3d09f53534ea385d55ced408f2b67059b16e4, 134daaba93193df9e988524b5cd2f52d15eb1993, 2f45a8d64fb4ed4830a4b3273834ecd6ca504896
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 Kernel2.6.38 up to, but not including, 5.4.294; 5.5 up to, but not including, 5.10.238; 5.11 up to, but not including, 5.15.185; 5.16 up to, but not including, 6.1.141; 6.2 up to, but not including, 6.6.93; 6.7 up to, but not including, 6.12.31; 6.13 up to, but not including, 6.14.9; 6.155.4.294, 5.10.238, 5.15.185, 6.1.141, 6.6.93, 6.12.31
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: crypto: algif_hash - fix double free in hash_accept If accept(2) is called on socket type algif_hash with MSG_MORE flag set and crypto_ahash_import fails, sk2 is freed. However, it is also freed in af_alg_release, leading to slab-use-after-free error.

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

The underlying weakness: Double Free

The product calls free() twice on the same memory address.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • Ensure that each allocation is freed only once. After freeing a chunk, set the pointer to NULL to ensure the pointer cannot be freed again. In complicated error conditions, be sure that clean-up routines respect the state of allocation properly. If the language is object oriented, ensure that object destructors delete each chunk of memory only once.
  • Use a static analysis tool to find double free instances.

More Double Free vulnerabilities (CWE-415)

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

Recent Double Free vulnerabilities

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