CVE-2025-39931

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2025-10-04. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.5
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.5Exploit: NoneExposed: 0

A fix is available — apply it.

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
EG Score
5.5(medium)
EG Risk
29(Track)
EG Risk 29/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity55% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS
4.1%
KEV
Not listed

Published

October 4, 2025

Last Modified

July 14, 2026

Advisory Details (8)

Auto-updated Jul 4, 2026
⚠️ Active exploitation confirmed. No patch confirmed yet.
generic🔴 Active Exploitation

SSA-082556

https://cert-portal.siemens.com/productcert/html/ssa-082556.html
generic

crypto: af_alg - Set merge to zero early in af_alg_sendmsg - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/db2b42425dfbde4983b0c20fb7cfa05f70e6a745
generic

crypto: af_alg - Set merge to zero early in af_alg_sendmsg - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/9574b2330dbd2b5459b74d3b5e9619d39299fc6f
generic

crypto: af_alg - Set merge to zero early in af_alg_sendmsg - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/6241b9e2809b12da9130894cf5beddf088dc1b8a
generic

crypto: af_alg - Set merge to zero early in af_alg_sendmsg - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/28f6f37abca7c5c9eb3959c66310f1d4d98b8aaf
generic

crypto: af_alg - Set merge to zero early in af_alg_sendmsg - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/24c1106504c625fabd3b7229611af617b4c27ac7
generic

crypto: af_alg - Set merge to zero early in af_alg_sendmsg - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/2374c11189ef704a3e4863646369f1b8e6a27d71
generic

crypto: af_alg - Set merge to zero early in af_alg_sendmsg - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/045ee26aa3920a47ec46d7fcb302420bf01fd753

Vendor Advisories for CVE-2025-39931(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(11)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-virtual-hwe-22.04-edge (6.8.0-106.106~22.04.1) @ jammy2026-05-21ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1049.52.1) @ noble2026-05-21ubuntu
ubuntulinux-tools-gcp-fips-6.8 (6.8.0-1052.55+fips1) @ noble2026-05-21ubuntu
ubuntulinux-tools-realtime-hwe-22.04 (6.8.1-1045.46~22.04.1) @ jammy2026-05-21ubuntu
ubuntulinux-tools-aws-edge (6.8.0-1050.53~22.04.1) @ jammy2026-05-21ubuntu
ubuntulinux-tools-azure-lts-24.04 (6.8.0-1051.57) @ noble2026-05-21ubuntu
ubuntulinux-tools-azure-edge (6.8.0-1051.57~22.04.1) @ jammy2026-05-21ubuntu
ubuntulinux-tools-azure-fips-6.8 (6.8.0-1052.58+fips1) @ noble2026-05-21ubuntu
ubuntulinux-tools-raspi-realtime-6.8 (6.8.0-2040.41) @ noble2026-05-21ubuntu
ubuntulinux-xilinx-zynqmp (6.8.0.1029.30) @ noble2026-05-21ubuntu
linuxKernel @ 5.10.260—osv

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(11)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 10× in last 7d / 46× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 123 total refreshes for this CVE.

  1. 2026-07-24 14:17 UTCEPSS rescore
  2. 2026-07-23 02:55 UTCEG score recompute
  3. 2026-07-22 14:07 UTCEPSS rescore
  4. 2026-07-22 14:07 UTCEPSS rescore
  5. 2026-07-21 15:24 UTCEPSS rescore
  6. 2026-07-20 17:07 UTCEPSS rescore
  7. 2026-07-19 14:30 UTCEPSS rescore
  8. 2026-07-19 14:30 UTCEPSS rescore
  9. 2026-07-18 10:04 UTCEPSS rescore
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  11. 2026-07-16 17:02 UTCEPSS rescore
  12. 2026-07-15 16:57 UTCEPSS rescore
  13. 2026-07-15 16:57 UTCEPSS rescore
  14. 2026-07-15 01:59 UTCEPSS rescore
  15. 2026-07-15 01:59 UTCEPSS rescore
  16. 2026-07-14 13:19 UTCNVD updateCVSS v3 → 5.5 · severity → MEDIUM
  17. 2026-07-14 13:11 UTCMITRE cvelistV5
  18. 2026-07-13 22:29 UTCEPSS rescore
  19. 2026-07-13 22:29 UTCEPSS rescore
  20. 2026-07-13 06:12 UTCEPSS rescore
  21. 2026-07-12 05:46 UTCEPSS rescore
  22. 2026-07-11 08:27 UTCEPSS rescore
  23. 2026-07-11 08:27 UTCEPSS rescore
  24. 2026-07-10 04:53 UTCOSV refresh
  25. 2026-07-09 19:09 UTCEPSS rescore
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  1. 2026-07-09 19:09 UTCEPSS rescore
  2. 2026-07-07 13:45 UTCEPSS rescore
  3. 2026-07-06 02:23 UTCEPSS rescore
  4. 2026-07-05 02:30 UTCEPSS rescore
  5. 2026-07-04 12:27 UTCNVD updateCVSS v3 → 5.5 · severity → MEDIUM
  6. 2026-07-04 12:16 UTCMITRE cvelistV5
  7. 2026-07-04 06:30 UTCEPSS rescore
  8. 2026-07-01 15:06 UTCEPSS rescore
  9. 2026-07-01 15:06 UTCEPSS rescore
  10. 2026-06-30 23:22 UTCEPSS rescore
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  12. 2026-06-29 14:06 UTCEPSS rescore
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  14. 2026-06-28 14:07 UTCEPSS rescore
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  16. 2026-06-28 04:55 UTCEPSS rescore
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  18. 2026-06-27 03:08 UTCEPSS rescore
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  20. 2026-06-25 13:49 UTCEPSS rescore
  21. 2026-06-25 13:49 UTCEPSS rescore
  22. 2026-06-24 14:04 UTCEPSS rescore
  23. 2026-06-24 14:04 UTCEPSS rescore
  24. 2026-06-23 21:32 UTCEPSS rescore
  25. 2026-06-23 21:32 UTCEPSS rescore
  26. 2026-06-22 14:25 UTCEPSS rescore
  27. 2026-06-22 14:25 UTCEPSS rescore
  28. 2026-06-21 15:22 UTCOSV refresh
  29. 2026-06-21 14:56 UTCEPSS rescore
  30. 2026-06-21 14:56 UTCEPSS rescore
  31. 2026-06-21 01:59 UTCEPSS rescore
  32. 2026-06-21 01:59 UTCEPSS rescore
  33. 2026-06-19 19:25 UTCEPSS rescore
  34. 2026-06-19 19:25 UTCEPSS rescore
  35. 2026-06-18 17:52 UTCEPSS rescore
  36. 2026-06-18 17:52 UTCEPSS rescore
  37. 2026-06-17 17:52 UTCEPSS rescore
  38. 2026-06-16 17:52 UTCEPSS rescore
  39. 2026-06-16 17:52 UTCEPSS rescore
  40. 2026-06-14 23:17 UTCEPSS rescore
  41. 2026-06-13 23:00 UTCEPSS rescore
  42. 2026-06-12 23:11 UTCEPSS rescore
  43. 2026-06-11 14:00 UTCEPSS rescore
  44. 2026-06-10 22:18 UTCEPSS rescore
  45. 2026-06-10 13:22 UTCEPSS rescore
  46. 2026-06-08 14:16 UTCEPSS rescore
  47. 2026-06-08 14:16 UTCEPSS rescore
  48. 2026-06-07 15:24 UTCEPSS rescore
  49. 2026-06-06 13:47 UTCEPSS rescore
  50. 2026-06-06 13:47 UTCEPSS rescore
  51. 2026-06-05 22:46 UTCEPSS rescore
  52. 2026-06-05 22:46 UTCEPSS rescore
  53. 2026-06-05 06:10 UTCEPSS rescore
  54. 2026-06-05 06:10 UTCEPSS rescore
  55. 2026-06-04 13:12 UTCEPSS rescore
  56. 2026-06-04 13:12 UTCEPSS rescore
  57. 2026-06-02 20:12 UTCEPSS rescore
  58. 2026-06-02 11:55 UTCOSV refresh
  59. 2026-06-01 13:51 UTCEPSS rescore
  60. 2026-06-01 13:51 UTCEPSS rescore
  61. 2026-05-31 22:30 UTCEPSS rescore
  62. 2026-05-31 22:30 UTCEPSS rescore
  63. 2026-05-31 00:16 UTCEPSS rescore
  64. 2026-05-29 13:44 UTCEPSS rescore
  65. 2026-05-28 13:44 UTCEPSS rescore
  66. 2026-05-28 13:44 UTCEPSS rescore
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  75. 2026-05-26 13:43 UTCEPSS rescore

Related CVEs(same product + same vendor + same CWE)

Frequently asked(5)

What is CVE-2025-39931?
CVE-2025-39931 is a medium vulnerability published on October 4, 2025. In the Linux kernel, the following vulnerability has been resolved: crypto: afalg - Set merge to zero early in afalg_sendmsg If an error causes afalgsendmsg to abort, ctx->merge may contain a garbage value from the previous loop. This may then trigger a crash on the next entry into afalgsendmsg…
When was CVE-2025-39931 disclosed?
CVE-2025-39931 was first published in the National Vulnerability Database on October 4, 2025, with the most recent update on July 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2025-39931 actively exploited?
CVE-2025-39931 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 4.1% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2025-39931?
CVE-2025-39931 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2025-39931?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2025-39931, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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