CVE-2026-31495

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-04-22. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

In the Linux kernel, the following vulnerability has been resolved:

netfilter: ctnetlink: use netlink policy range checks

Replace manual range and mask validations with netlink policy annotations in ctnetlink code paths, so that the netlink core rejects invalid values early and can generate extack errors.

  • CTA_PROTOINFO_TCP_STATE: reject values > TCP_CONNTRACK_SYN_SENT2 at
policy level, removing the manual >= TCP_CONNTRACK_MAX check.
  • CTA_PROTOINFO_TCP_WSCALE_ORIGINAL/REPLY: reject values > TCP_MAX_WSCALE
(14). The normal TCP option parsing path already clamps to this value, but the ctnetlink path accepted 0-255, causing undefined behavior when used as a u32 shift count.
  • CTA_FILTER_ORIG_FLAGS/REPLY_FLAGS: use NLA_POLICY_MASK with
CTA_FILTER_F_ALL, removing the manual mask checks.
  • CTA_EXPECT_FLAGS: use NLA_POLICY_MASK with NF_CT_EXPECT_MASK, adding
a new mask define grouping all valid expect flags.

Extracted from a broader nf-next patch by Florian Westphal, scoped to ctnetlink for the fixes tree.

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 PROB
0%
EPSS %ILE
3%
KEV
Not listed

Published

April 22, 2026

Last Modified

July 14, 2026

Advisory Details (10)

Auto-updated Jul 19, 2026
⚠️ Active exploitation confirmed. No patch confirmed yet.
generic🔴 Active Exploitation

SSA-082556

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

SSA-019113

https://cert-portal.siemens.com/productcert/html/ssa-019113.html
generic

netfilter: ctnetlink: use netlink policy range checks - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/fcec5ce2d73a41668b24e3f18c803541602a59f6
generic

netfilter: ctnetlink: use netlink policy range checks - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/c6cb41eaae875501eaaa487b8db6539feb092292
generic

netfilter: ctnetlink: use netlink policy range checks - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/8f15b5071b4548b0aafc03b366eb45c9c6566704
generic

netfilter: ctnetlink: use netlink policy range checks - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/675c913b940488a84effdeeac5a1cfb657b59804
generic

netfilter: ctnetlink: use netlink policy range checks - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/4f7d25f3f0786402ba48ff7d13b6241d77d975f5
generic

netfilter: ctnetlink: use netlink policy range checks - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/45c33e79ae705b7af97e3117672b6cd258dd0b1b
generic

netfilter: ctnetlink: use netlink policy range checks - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/435b576cd2faa75154777868f8cbb73bf71644d3
generic

netfilter: ctnetlink: use netlink policy range checks - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/2ef71307c86a9f866d6e28f1a0c06e2e9d794474

Vendor Advisories for CVE-2026-31495(2)

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

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
linuxKernel @ 5.10.253—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.

Affected Packages

(5 across 4 ecosystems)
Debian:11(2)
PackageVulnerable rangeFixed inDependents
linux5.10.103-1 ... 5.10.92-2 (53 versions)5.10.257-1—
linux-6.16.1.106-3~deb11u1 ... 6.1.164-1~deb11u1 (16 versions)6.1.170-1~deb11u1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 6.1.99-1 (48 versions)6.1.170-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.85-1~bpo12+1 (17 versions)6.12.85-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 6.19~rc8-1~exp1 (121 versions)6.19.11-1—

Additional Vendor Advisories

(24)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 6× in last 7d / 48× 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 207 total refreshes for this CVE.

  1. 2026-09-04 05:06 UTCEPSS rescore
  2. 2026-09-02 14:11 UTCEPSS rescore
  3. 2026-09-02 03:04 UTCOSV refresh
  4. 2026-09-01 13:53 UTCEPSS rescore
  5. 2026-08-30 19:17 UTCEPSS rescore
  6. 2026-08-30 01:22 UTCEPSS rescore
  7. 2026-08-28 21:41 UTCEPSS rescore
  8. 2026-08-27 14:25 UTCEPSS rescore
  9. 2026-08-26 14:46 UTCEPSS rescore
  10. 2026-08-25 13:49 UTCEPSS rescore
  11. 2026-08-24 14:17 UTCEPSS rescore
  12. 2026-08-23 00:19 UTCEPSS rescore
  13. 2026-08-21 23:49 UTCEPSS rescore
  14. 2026-08-20 22:55 UTCEPSS rescore
  15. 2026-08-20 22:55 UTCEPSS rescore
  16. 2026-08-19 17:03 UTCEPSS rescore
  17. 2026-08-18 13:48 UTCEPSS rescore
  18. 2026-08-17 13:47 UTCEPSS rescore
  19. 2026-08-16 14:56 UTCEPSS rescore
  20. 2026-08-16 05:59 UTCEG score recompute
  21. 2026-08-16 05:59 UTCVendor advisory
  22. 2026-08-16 05:59 UTCGHSA enrichment
  23. 2026-08-16 02:14 UTCEPSS rescore
  24. 2026-08-15 01:30 UTCEPSS rescore
  25. 2026-08-14 04:19 UTCEG score recompute
Show 75 more
  1. 2026-08-14 04:19 UTCVendor advisory
  2. 2026-08-14 04:19 UTCGHSA enrichment
  3. 2026-08-13 22:00 UTCEPSS rescore
  4. 2026-08-12 18:30 UTCEG score recompute
  5. 2026-08-12 18:30 UTCVendor advisory
  6. 2026-08-12 18:30 UTCGHSA enrichment
  7. 2026-08-12 13:50 UTCEPSS rescore
  8. 2026-08-11 04:38 UTCEG score recompute
  9. 2026-08-11 04:38 UTCVendor advisory
  10. 2026-08-11 04:38 UTCGHSA enrichment
  11. 2026-08-11 00:00 UTCEPSS rescore
  12. 2026-08-10 04:06 UTCEG score recompute
  13. 2026-08-10 04:06 UTCVendor advisory
  14. 2026-08-10 04:06 UTCGHSA enrichment
  15. 2026-08-09 13:46 UTCEPSS rescore
  16. 2026-08-09 03:33 UTCEG score recompute
  17. 2026-08-09 03:33 UTCVendor advisory
  18. 2026-08-09 03:33 UTCGHSA enrichment
  19. 2026-08-08 16:37 UTCEPSS rescore
  20. 2026-08-07 12:49 UTCEG score recompute
  21. 2026-08-07 12:49 UTCVendor advisory
  22. 2026-08-07 12:49 UTCGHSA enrichment
  23. 2026-08-06 13:46 UTCEPSS rescore
  24. 2026-08-05 23:05 UTCEG score recompute
  25. 2026-08-05 23:05 UTCVendor advisory
  26. 2026-08-05 23:05 UTCGHSA enrichment
  27. 2026-08-05 19:17 UTCEPSS rescore
  28. 2026-08-04 15:10 UTCEPSS rescore
  29. 2026-08-04 10:38 UTCEPSS rescore
  30. 2026-08-03 21:14 UTCEG score recompute
  31. 2026-08-03 21:14 UTCVendor advisory
  32. 2026-08-03 21:14 UTCGHSA enrichment
  33. 2026-08-03 10:36 UTCEPSS rescore
  34. 2026-08-02 12:10 UTCEG score recompute
  35. 2026-08-02 12:10 UTCVendor advisory
  36. 2026-08-02 12:10 UTCGHSA enrichment
  37. 2026-08-02 02:27 UTCEPSS rescore
  38. 2026-08-01 04:16 UTCEPSS rescore
  39. 2026-07-30 16:27 UTCEPSS rescore
  40. 2026-07-30 01:30 UTCEPSS rescore
  41. 2026-07-28 15:36 UTCEPSS rescore
  42. 2026-07-25 14:18 UTCEPSS rescore
  43. 2026-07-25 14:17 UTCEPSS rescore
  44. 2026-07-24 14:17 UTCEPSS rescore
  45. 2026-07-23 14:18 UTCEPSS rescore
  46. 2026-07-23 14:18 UTCEPSS rescore
  47. 2026-07-23 03:08 UTCEG score recompute
  48. 2026-07-22 14:08 UTCEPSS rescore
  49. 2026-07-22 14:08 UTCEPSS rescore
  50. 2026-07-21 15:24 UTCEPSS rescore
  51. 2026-07-21 15:24 UTCEPSS rescore
  52. 2026-07-20 17:08 UTCEPSS rescore
  53. 2026-07-20 17:08 UTCEPSS rescore
  54. 2026-07-19 23:48 UTCOSV refresh
  55. 2026-07-19 14:31 UTCEPSS rescore
  56. 2026-07-19 14:31 UTCEPSS rescore
  57. 2026-07-19 02:29 UTCEPSS rescore
  58. 2026-07-18 10:04 UTCEPSS rescore
  59. 2026-07-18 10:04 UTCEPSS rescore
  60. 2026-07-16 17:03 UTCEPSS rescore
  61. 2026-07-16 17:03 UTCEPSS rescore
  62. 2026-07-15 16:57 UTCEPSS rescore
  63. 2026-07-15 16:57 UTCEPSS rescore
  64. 2026-07-15 02:00 UTCEPSS rescore
  65. 2026-07-15 02:00 UTCEPSS rescore
  66. 2026-07-14 13:19 UTCNVD updateCVSS v3 → 5.5 · severity → MEDIUM
  67. 2026-07-14 13:11 UTCMITRE cvelistV5
  68. 2026-07-13 22:30 UTCEPSS rescore
  69. 2026-07-13 06:13 UTCEPSS rescore
  70. 2026-07-13 06:13 UTCEPSS rescore
  71. 2026-07-12 05:46 UTCEPSS rescore
  72. 2026-07-11 08:27 UTCEPSS rescore
  73. 2026-07-09 19:10 UTCEPSS rescore
  74. 2026-07-08 15:15 UTCEPSS rescore
  75. 2026-07-07 13:46 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-31495?
CVE-2026-31495 is a medium vulnerability published on April 22, 2026. In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: use netlink policy range checks Replace manual range and mask validations with netlink policy annotations in ctnetlink code paths, so that the netlink core rejects invalid values early and can generate extack…
When was CVE-2026-31495 disclosed?
CVE-2026-31495 was first published in the National Vulnerability Database on April 22, 2026, 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-2026-31495 actively exploited?
CVE-2026-31495 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 97.2% of all scored CVEs.
What is the CVSS score of CVE-2026-31495?
CVE-2026-31495 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-31495?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-31495, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-31495

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