CVE-2026-31685

CRITICALNVD 9.49.4—
EchelonGraph scoreMEDIUM confidence

Score 9.4 from GitHub Security Advisory (severity: CRITICAL) published 2026-04-25. NVD baseline CVSS 9.4; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
9.4EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.4Exploit: None knownExposed: 0

A fix is available — apply it.

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

netfilter: ip6t_eui64: reject invalid MAC header for all packets

eui64_mt6() derives a modified EUI-64 from the Ethernet source address and compares it with the low 64 bits of the IPv6 source address.

The existing guard only rejects an invalid MAC header when par->fragoff != 0. For packets with par->fragoff == 0, eui64_mt6() can still reach eth_hdr(skb) even when the MAC header is not valid.

Fix this by removing the par->fragoff != 0 condition so that packets with an invalid MAC header are rejected before accessing eth_hdr(skb).

CVSS v3
9.4
EG Score
9.4(medium)
EG Risk
47(Track)
EG Risk 47/100SSVC: 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
Severity94% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
27%
KEV
Not listed

Published

April 25, 2026

Last Modified

August 5, 2026

Advisory Details (8)

Auto-updated Sep 5, 2026
No patch confirmed yet.
generic

netfilter: ip6t_eui64: reject invalid MAC header for all packets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/fdce0b3590f724540795b874b4c8850c90e6b0a8
generic

netfilter: ip6t_eui64: reject invalid MAC header for all packets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/309ae3e9a51a69699ca94eac5fac5688fa562d55
generic

netfilter: ip6t_eui64: reject invalid MAC header for all packets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/807d6ee15804df6f01a35c910f09612e858739a6
generic

netfilter: ip6t_eui64: reject invalid MAC header for all packets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/9eda5478746ef7dc0e4e537b5a5e4b0ca1027091
generic

netfilter: ip6t_eui64: reject invalid MAC header for all packets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/288138418bef956f8b295751a4536c60f0e89f4a
generic

netfilter: ip6t_eui64: reject invalid MAC header for all packets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d5603591373441fecf9951833d6d873e09320f08
generic

netfilter: ip6t_eui64: reject invalid MAC header for all packets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/7d6a57411caf54df025860c9b1a82cd42d57a562
generic

netfilter: ip6t_eui64: reject invalid MAC header for all packets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/4d75bc2cd093bf5803edf512c099bfb220fd6459

Vendor Advisories for CVE-2026-31685(16)

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

Patch Availability(15)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatkernel-rt-0:3.10.0-1160.155.1.rt56.1307.el72026-07-17redhat
redhatkernel-0:4.18.0-477.147.1.el8_82026-06-17redhat
redhatkernel-0:5.14.0-284.176.1.el9_22026-06-17redhat
redhatkernel-rt-0:5.14.0-284.176.1.rt14.461.el9_22026-06-17redhat
redhatkernel-0:4.18.0-305.194.1.el8_42026-06-17redhat
redhatkernel-0:4.18.0-372.195.1.el8_62026-06-12redhat
redhatkernel-0:3.10.0-1160.151.1.el72026-06-10redhat
redhatkernel-0:6.12.0-55.77.1.el10_02026-06-08redhat
redhatkernel-0:5.14.0-427.129.1.el9_42026-06-04redhat
redhatkernel-0:5.14.0-570.119.1.el9_62026-06-04redhat
redhatkernel-0:6.12.0-211.18.1.el10_22026-05-28redhat
redhatkernel-rt-0:4.18.0-553.126.1.rt7.467.el8_102026-05-28redhat
redhatkernel-0:4.18.0-553.126.1.el8_102026-05-28redhat
redhatkernel-0:5.14.0-687.12.1.el9_82026-05-28redhat
linuxKernel @ 5.10.258—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 (54 versions)5.10.259-1—
linux-6.16.1.106-3~deb11u1 ... 6.1.174-1~deb11u1 (20 versions)6.1.176-1~deb11u1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 6.1.99-1 (53 versions)6.1.176-1—
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 (126 versions)6.19.14-1—

Additional Vendor Advisories

(10)

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 / 79× 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 397 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-31685?
CVE-2026-31685 is a critical vulnerability published on April 25, 2026. In the Linux kernel, the following vulnerability has been resolved: netfilter: ip6t_eui64: reject invalid MAC header for all packets eui64_mt6() derives a modified EUI-64 from the Ethernet source address and compares it with the low 64 bits of the IPv6 source address. The existing guard only…
When was CVE-2026-31685 disclosed?
CVE-2026-31685 was first published in the National Vulnerability Database on April 25, 2026, with the most recent update on August 5, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-31685 actively exploited?
CVE-2026-31685 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 73.4% of all scored CVEs.
What is the CVSS score of CVE-2026-31685?
CVE-2026-31685 has a CVSS v3 base score of 9.4 (NVD).
How do I remediate CVE-2026-31685?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-31685, 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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