Unknown

CVE-2026-80890 — sctp: reject stale cookies with mismatched verification tags

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.

Published Sep 4, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+1

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.18%

ahead of 8% of scored CVEs · Oct 26, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < f6e3cc296372accad4ee57405195021231ef4bcb≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < c151daba0ceb1fb068a215b07de89fb1eb5f87bc≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < 817cffdbdbdf50e1f2b016599d1897de3ca54964≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < 61baa5020b0afb41bfd97f8f6ce5e336c4a4546e≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < c68557a49e960dbcdede22c7a9b488603078b8b4≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < a0d1693923f41d6f49083aa2446686aed09d1d79≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < 35c279113498d19a8734e2aae67b951b9b20f634≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < 9d8da8e0a9bce4a340af60dd0446bc7eb8d07587 and 1 more version 2.6.12	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 15, 2026 → Oct 26, 2026 · 11 reading(s) · max 0.18%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 15, 2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Sep 4, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

8 on the record

git.kernel.org/stable/c/a0d1693923f41d6f49083aa2446686aed09d1d79
NIST National Vulnerability Database
git.kernel.org/stable/c/c151daba0ceb1fb068a215b07de89fb1eb5f87bc
NIST National Vulnerability Database
git.kernel.org/stable/c/c68557a49e960dbcdede22c7a9b488603078b8b4
NIST National Vulnerability Database
git.kernel.org/stable/c/817cffdbdbdf50e1f2b016599d1897de3ca54964
NIST National Vulnerability Database
git.kernel.org/stable/c/61baa5020b0afb41bfd97f8f6ce5e336c4a4546e
NIST National Vulnerability Database
git.kernel.org/stable/c/9d8da8e0a9bce4a340af60dd0446bc7eb8d07587
NIST National Vulnerability Database
git.kernel.org/stable/c/f6e3cc296372accad4ee57405195021231ef4bcb
NIST National Vulnerability Database
git.kernel.org/stable/c/35c279113498d19a8734e2aae67b951b9b20f634
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Unknown CVE-2026-99092 riscv: patch: fix handling of bpf-jit execmem addresses 19h
Unknown CVE-2026-99093 mm: don't schedule deferred kernel page table freeing while booting 19h
Unknown CVE-2026-99095 drm/vc4: drain the hangcheck timer and works on V3D unbind 19h
Unknown CVE-2026-99096 io_uring/register: don't exempt disabled rings from task restrictions 19h
Unknown CVE-2026-99097 tee: shm: reject zero-sized allocations in tee_dyn_shm_alloc_helper() 19h
Unknown CVE-2026-99098 dm-integrity: fix buffer overflow in inline mode with large tag size 19h

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-80890 is "sctp: reject stale cookies with mismatched verification tags", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.18% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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