CVE-2026-80890: Linux kernel · sctp: reject stale cookies with mismatched verification tags
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in f6e3cc296372accad4ee57405195021231ef4bcb : update Linux kernel when convenient.
Data as of 6 Nov 2026, 17:34 UTC
Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD
Thin evidence
One scorer or none- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-11-06.
- Patch
- Available – fixed in f6e3cc296372accad4ee57405195021231ef4bcb, c68557a49e960dbcdede22c7a9b488603078b8b4, c151daba0ceb1fb068a215b07de89fb1eb5f87bc +5
Exploitation evidence
Disclosed: evidence found.
CVE published 4 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 6 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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AI-suggested
A fix is available and has been applied in the Linux kernel. Users should update to a fixed kernel version containing the relevant patches identified by the provided commit hashes. No additional mitigation is required beyond applying the official fix.
Description
A vulnerability in the Linux kernel SCTP implementation allowed stale cookies with mismatched verification tags to be accepted, bypassing proper expiration checks. This flaw permitted replayed expired cookies to restart existing associations improperly. The issue was addressed by enforcing cookie expiration checks unless both verification tags match, aligning with RFC 9260 requirements.
References
- git.kernel.org/stable/c/f6e3cc296372accad4ee57405195021231ef4bcb (opens in a new tab)
- git.kernel.org/stable/c/c151daba0ceb1fb068a215b07de89fb1eb5f87bc (opens in a new tab)
- git.kernel.org/stable/c/817cffdbdbdf50e1f2b016599d1897de3ca54964 (opens in a new tab)
- git.kernel.org/stable/c/61baa5020b0afb41bfd97f8f6ce5e336c4a4546e (opens in a new tab)
- git.kernel.org/stable/c/c68557a49e960dbcdede22c7a9b488603078b8b4 (opens in a new tab)
- git.kernel.org/stable/c/a0d1693923f41d6f49083aa2446686aed09d1d79 (opens in a new tab)
- git.kernel.org/stable/c/35c279113498d19a8734e2aae67b951b9b20f634 (opens in a new tab)
- git.kernel.org/stable/c/9d8da8e0a9bce4a340af60dd0446bc7eb8d07587 (opens in a new tab)