CVE-2026-31637

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-04-24. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.8Exploit: 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:

rxrpc: reject undecryptable rxkad response tickets

rxkad_decrypt_ticket() decrypts the RXKAD response ticket and then parses the buffer as plaintext without checking whether crypto_skcipher_decrypt() succeeded.

A malformed RESPONSE can therefore use a non-block-aligned ticket length, make the decrypt operation fail, and still drive the ticket parser with attacker-controlled bytes.

Check the decrypt result and abort the connection with RXKADBADTICKET when ticket decryption fails.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
49(Track)
EG Risk 49/100SSVC: 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
Severity98% × 45%
Exploitation1% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
43%
KEV
Not listed

Published

April 24, 2026

Last Modified

August 5, 2026

Advisory Details (8)

Auto-updated Sep 16, 2026
No patch confirmed yet.
generic

rxrpc: reject undecryptable rxkad response tickets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/fe4447cd95623b1cfacc15f280aab73a6d7340b2
generic

rxrpc: reject undecryptable rxkad response tickets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/58fcd1b156152613ba00a064a129fb69507ddd7d
generic

rxrpc: reject undecryptable rxkad response tickets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/22f6258e7b31dba9bf88dce4e3ee7f0f20072e60
generic

rxrpc: reject undecryptable rxkad response tickets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/a149dcae23309df9de1c3b6b5d468610ef5ab7de
generic

rxrpc: reject undecryptable rxkad response tickets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/47073aab8a3a5a7b41c9bd37d2a3dcbeeccd6c8a
generic

rxrpc: reject undecryptable rxkad response tickets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b3a808cd0790b5075aaa2bc3588edf02cd71d352
generic

rxrpc: reject undecryptable rxkad response tickets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/a75b3b361dd481d942c5f259a82d59718a41092c
generic

rxrpc: reject undecryptable rxkad response tickets - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/252157d939d179b5d767cb860ff8fa7f8723b67a

Vendor Advisories for CVE-2026-31637(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 @ 5.10.258—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 (127 versions)6.19.13-1—

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 / 28× 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 409 total refreshes for this CVE.

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

Related CVEs(same product + same vendor)

Frequently asked(5)

What is CVE-2026-31637?
CVE-2026-31637 is a critical vulnerability published on April 24, 2026. In the Linux kernel, the following vulnerability has been resolved: rxrpc: reject undecryptable rxkad response tickets rxkaddecryptticket() decrypts the RXKAD response ticket and then parses the buffer as plaintext without checking whether cryptoskcipherdecrypt() succeeded. A malformed RESPONSE can…
When was CVE-2026-31637 disclosed?
CVE-2026-31637 was first published in the National Vulnerability Database on April 24, 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-2026-31637 actively exploited?
CVE-2026-31637 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 57.2% of all scored CVEs.
What is the CVSS score of CVE-2026-31637?
CVE-2026-31637 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-31637?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-31637, 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-2026-31637

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