Vulnerability-Lookup

FKIE_CVE-2025-39931

Vulnerability from fkie_nvd - Published: 2025-10-04 08:15 - Updated: 2026-01-27 18:50

Severity ?

5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Summary

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.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/045ee26aa3920a47ec46d7fcb302420bf01fd753	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/2374c11189ef704a3e4863646369f1b8e6a27d71	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/24c1106504c625fabd3b7229611af617b4c27ac7	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/6241b9e2809b12da9130894cf5beddf088dc1b8a	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/9574b2330dbd2b5459b74d3b5e9619d39299fc6f	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	6.17
linux	linux_kernel	6.17
linux	linux_kernel	6.17
linux	linux_kernel	6.17
linux	linux_kernel	6.17
linux	linux_kernel	6.17

JSON

To clipboard

{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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              "vulnerable": true
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  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: af_alg - Set merge to zero early in af_alg_sendmsg\n\nIf an error causes af_alg_sendmsg to abort, ctx-\u003emerge may contain\na garbage value from the previous loop.  This may then trigger a\ncrash on the next entry into af_alg_sendmsg when it attempts to do\na merge that can\u0027t be done.\n\nFix this by setting ctx-\u003emerge to zero near the start of the loop."
    }
  ],
  "id": "CVE-2025-39931",
  "lastModified": "2026-01-27T18:50:21.797",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2025-10-04T08:15:45.827",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-908"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

CVE-2025-39931 (GCVE-0-2025-39931)

Vulnerability from cvelistv5 – Published: 2025-10-04 07:30 – Updated: 2025-10-04 07:30

Title

crypto: af_alg - Set merge to zero early in af_alg_sendmsg

Summary

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/6241b9e2809b12da9…
	https://git.kernel.org/stable/c/2374c11189ef704a3…
	https://git.kernel.org/stable/c/24c1106504c625fab…
	https://git.kernel.org/stable/c/045ee26aa3920a47e…
	https://git.kernel.org/stable/c/9574b2330dbd2b545…

Impacted products

Vendor

Product

Version

Linux

Affected: 8ff590903d5fc7f5a0a988c38267a3d08e6393a2 , < 6241b9e2809b12da9130894cf5beddf088dc1b8a (git)
Affected: 8ff590903d5fc7f5a0a988c38267a3d08e6393a2 , < 2374c11189ef704a3e4863646369f1b8e6a27d71 (git)
Affected: 8ff590903d5fc7f5a0a988c38267a3d08e6393a2 , < 24c1106504c625fabd3b7229611af617b4c27ac7 (git)
Affected: 8ff590903d5fc7f5a0a988c38267a3d08e6393a2 , < 045ee26aa3920a47ec46d7fcb302420bf01fd753 (git)
Affected: 8ff590903d5fc7f5a0a988c38267a3d08e6393a2 , < 9574b2330dbd2b5459b74d3b5e9619d39299fc6f (git)

Linux

Affected: 2.6.38
Unaffected: 0 , < 2.6.38 (semver)
Unaffected: 6.1.154 , ≤ 6.1.* (semver)
Unaffected: 6.6.108 , ≤ 6.6.* (semver)
Unaffected: 6.12.49 , ≤ 6.12.* (semver)
Unaffected: 6.16.9 , ≤ 6.16.* (semver)
Unaffected: 6.17 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
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        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "crypto/af_alg.c"
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Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

FKIE_CVE-2025-39931

CVE-2025-39931 (GCVE-0-2025-39931)

Tags

Sightings

Nomenclature