CVE-2026-31637 (GCVE-0-2026-31637)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:44 – Updated: 2026-10-19 18:56
VLAI
Title
rxrpc: reject undecryptable rxkad response tickets
Summary
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.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-16 15:11 UTC
CWE
  • CWE-754 - Improper Check for Unusual or Exceptional Conditions
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6641 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 17926a79320afa9b95df6b977b40cca6d8713cea , < 252157d939d179b5d767cb860ff8fa7f8723b67a (git)
Affected: 17926a79320afa9b95df6b977b40cca6d8713cea , < a75b3b361dd481d942c5f259a82d59718a41092c (git)
Affected: 17926a79320afa9b95df6b977b40cca6d8713cea , < b3a808cd0790b5075aaa2bc3588edf02cd71d352 (git)
Affected: 17926a79320afa9b95df6b977b40cca6d8713cea , < 47073aab8a3a5a7b41c9bd37d2a3dcbeeccd6c8a (git)
Affected: 17926a79320afa9b95df6b977b40cca6d8713cea , < a149dcae23309df9de1c3b6b5d468610ef5ab7de (git)
Affected: 17926a79320afa9b95df6b977b40cca6d8713cea , < 22f6258e7b31dba9bf88dce4e3ee7f0f20072e60 (git)
Affected: 17926a79320afa9b95df6b977b40cca6d8713cea , < 58fcd1b156152613ba00a064a129fb69507ddd7d (git)
Affected: 17926a79320afa9b95df6b977b40cca6d8713cea , < fe4447cd95623b1cfacc15f280aab73a6d7340b2 (git)
guessed Create a notification for this product.
Linux Linux Affected: 2.6.22
Unaffected: 0 , < 2.6.22 (semver)
Unaffected: 5.10.258 , ≤ 5.10.* (semver)
Unaffected: 5.15.209 , ≤ 5.15.* (semver)
Unaffected: 6.1.175 , ≤ 6.1.* (semver)
Unaffected: 6.6.135 , ≤ 6.6.* (semver)
Unaffected: 6.12.82 , ≤ 6.12.* (semver)
Unaffected: 6.18.23 , ≤ 6.18.* (semver)
Unaffected: 6.19.13 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem Affected: 0 , < * (custom)
guessed Create a notification for this product.
Show details on NVD website
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}



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Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

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Sightings

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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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

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