CVE-2025-39931

In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - Set merge to zero early in af_alg_sendmsg If an error causes af_alg_sendmsg to abort, ctx->merge may contain a garbage value from the previous loop. This may then trigger a crash on the next entry into af_alg_sendmsg when it attempts to do a merge that can't be done. Fix this by setting ctx->merge to zero near the start of the loop.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/045ee26aa3920a47ec46d7fcb302420bf01fd753	Patch
https://git.kernel.org/stable/c/2374c11189ef704a3e4863646369f1b8e6a27d71	Patch
https://git.kernel.org/stable/c/24c1106504c625fabd3b7229611af617b4c27ac7	Patch
https://git.kernel.org/stable/c/6241b9e2809b12da9130894cf5beddf088dc1b8a	Patch
https://git.kernel.org/stable/c/9574b2330dbd2b5459b74d3b5e9619d39299fc6f	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc1::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc2::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc3::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc4::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc5::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc6::::::

History

No history.

Information

Published : 2025-10-04 08:15

Updated : 2026-01-27 18:50

NVD link : CVE-2025-39931

Mitre link : CVE-2025-39931

CVE.ORG link : CVE-2025-39931

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-908

Use of Uninitialized Resource

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