CVE-2026-80890Network attack vectorHinoki check available

Remote association restart via expired cookie replay

Published Sep 4, 2026 · Updated Sep 4, 2026

SCTP state-validation failure in Linux allows remote attackers to restart an existing association by replaying an expired State Cookie. sctp_unpack_cookie() skips expiration validation whenever an association exists, allowing a mismatched Action A cookie to reach sctp_sf_do_dupcook_a(). Exploitation requires a previously issued cookie for an existing association; the demonstrated consequence is association restart, with no published confidentiality or data-integrity impact.

CVSS severityUnavailable
Unscored
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

SCTP state-validation failure in Linux allows remote attackers to restart an existing association by replaying an expired State Cookie. sctp_unpack_cookie() skips expiration validation whenever an association exists, allowing a mismatched Action A cookie to reach sctp_sf_do_dupcook_a(). Exploitation requires a previously issued cookie for an existing association; the demonstrated consequence is association restart, with no published confidentiality or data-integrity impact.

The record

CVE
CVE-2026-80890
Published
Sep 4, 2026
Updated
Sep 4, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 4, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <35c279113498d19a8734e2aae67b951b9b20f634
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <61baa5020b0afb41bfd97f8f6ce5e336c4a4546e
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <817cffdbdbdf50e1f2b016599d1897de3ca54964
  4. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <9d8da8e0a9bce4a340af60dd0446bc7eb8d07587
  5. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a0d1693923f41d6f49083aa2446686aed09d1d79
  6. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c151daba0ceb1fb068a215b07de89fb1eb5f87bc
  7. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c68557a49e960dbcdede22c7a9b488603078b8b4
  8. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <f6e3cc296372accad4ee57405195021231ef4bcb
  9. Affected versionversion=2.6.12

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <35c279113498d19a8734e2aae67b951b9b20f634; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <61baa5020b0afb41bfd97f8f6ce5e336c4a4546e; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <817cffdbdbdf50e1f2b016599d1897de3ca54964; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <9d8da8e0a9bce4a340af60dd0446bc7eb8d07587; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a0d1693923f41d6f49083aa2446686aed09d1d79; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c151daba0ceb1fb068a215b07de89fb1eb5f87bc; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c68557a49e960dbcdede22c7a9b488603078b8b4; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <f6e3cc296372accad4ee57405195021231ef4bcb; version=2.6.12

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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