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Back to active CVEs
Unknown severity ยท Source severity not reportedCVE-2026-80890

sctp: reject stale cookies with mismatched verification tagsCVE-2026-80890

Answer in brief

CVE-2026-80890 records a Unknown severity vulnerability in sctp: reject stale cookies with mismatched verification tags. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 4, 2026Updated Sep 4, 2026Source checked Oct 19, 2026First seen by HOL Sep 4, 2026Material review Sep 4, 2026
Upstream Advisory

Key facts

Risk
Unknown severitySource severity not reported
Exploitation
Not marked as known exploited
Affected software
2 mapped packages or products
Fix availability
Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
PackageAffected rangeFixed version
Linux/Linuxgeneric>=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <f6e3cc296372accad4ee57405195021231ef4bcb || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c151daba0ceb1fb068a215b07de89fb1eb5f87bc || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <817cffdbdbdf50e1f2b016599d1897de3ca54964 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <61baa5020b0afb41bfd97f8f6ce5e336c4a4546e || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c68557a49e960dbcdede22c7a9b488603078b8b4 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a0d1693923f41d6f49083aa2446686aed09d1d79 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <35c279113498d19a8734e2aae67b951b9b20f634 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <9d8da8e0a9bce4a340af60dd0446bc7eb8d07587f6e3cc296372accad4ee57405195021231ef4bcb, c151daba0ceb1fb068a215b07de89fb1eb5f87bc, 817cffdbdbdf50e1f2b016599d1897de3ca54964, 61baa5020b0afb41bfd97f8f6ce5e336c4a4546e, c68557a49e960dbcdede22c7a9b488603078b8b4, a0d1693923f41d6f49083aa2446686aed09d1d79, 35c279113498d19a8734e2aae67b951b9b20f634, 9d8da8e0a9bce4a340af60dd0446bc7eb8d07587
Linux/Linuxgeneric2.6.12Not reported

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
  2. 2Review the reported fix. Update Linux/Linux to f6e3cc296372accad4ee57405195021231ef4bcb if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Sep 4, 2026

    Evidence: source:cvelist:source_dates:source-dates:record
  2. Source modified

    Sep 4, 2026

    Evidence: source:cvelist:source_dates:source-dates:record
  3. First seen by HOL

    Sep 4, 2026

Sources and claim methodology

  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
Upstream source description

In the Linux kernel, the following vulnerability has been resolved: sctp: reject stale cookies with mismatched verification tags sctp_unpack_cookie() skips cookie expiration checks whenever an association already exists. This is broader than the exception in RFC 9260 Section 5.2.4. For an existing association, Section 5.2.4 permits an expired State Cookie only when both Verification Tags in the cookie match the current association. Otherwise, the packet SHOULD be discarded and a Stale Cookie ERROR MUST be sent. The broad check lets an expired Action A restart cookie reach sctp_sf_do_dupcook_a(). In a runtime test with the default 60 second cookie lifetime, replaying such a cookie after 65 seconds returned a COOKIE-ACK and restarted the association. Check cookie expiration unless both Verification Tags match. This preserves the Action D exception for a lost COOKIE ACK while rejecting expired cookies in all other cases.

Quoted source text, attributed separately from HOL analysis.

Record context

Vulnerability class
Vulnerability
EPSS
Not reported
CWE IDs
Not reported
Source
CVE List V5
Source checked
Oct 19, 2026
References
8 linked sources
Open source record