Vulnerability-Lookup

GHSA-6F65-MFMH-H759

Vulnerability from github – Published: 2026-08-27 06:31 – Updated: 2026-08-27 06:31

Details

In the Linux kernel, the following vulnerability has been resolved:

mptcp: options: reset DSS fields in case of unexpected size

A remote peer could send a malformed DSS with a wrong size, followed by another DSS or MPC + Data. In this case, the first suboption will be ignored, but leaving some fields written, which could lead to inconsistency or access uninitialized data.

Explicitly reset the fields that could have been modified in case of unexpected size.

Severity

9.8 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-80586"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-26T15:17:14Z",
    "severity": "CRITICAL"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: options: reset DSS fields in case of unexpected size\n\nA remote peer could send a malformed DSS with a wrong size, followed by\nanother DSS or MPC + Data. In this case, the first suboption will be\nignored, but leaving some fields written, which could lead to\ninconsistency or access uninitialized data.\n\nExplicitly reset the fields that could have been modified in case of\nunexpected size.",
  "id": "GHSA-6f65-mfmh-h759",
  "modified": "2026-08-27T06:31:33Z",
  "published": "2026-08-27T06:31:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-80586"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/15e35fdad7a5576bf3f1c8d688877aeb5d1b506b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/192878df582c51d440bf7b91a15f297f29f2b596"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1fade1b2ac5b1a4948e538fae7313bea57b5ac36"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/26dac5c9ffb20812b475fdf253eb04fab99cff3b"
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      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/27ed642a4e7e4b5df4b8522c72c457a67e052493"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/35772b4981f38ba8059372cde8753e8e477e98ec"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4e80eff5c1c893aca2ac1d202f0b256d2e52ecde"
    },
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      "type": "WEB",
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      "type": "CVSS_V3"
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}

CVE-2026-80586 (GCVE-0-2026-80586)

Vulnerability from cvelistv5 – Published: 2026-08-26 14:37 – Updated: 2026-10-16 19:26

Title

mptcp: options: reset DSS fields in case of unexpected size

Summary

In the Linux kernel, the following vulnerability has been resolved: mptcp: options: reset DSS fields in case of unexpected size A remote peer could send a malformed DSS with a wrong size, followed by another DSS or MPC + Data. In this case, the first suboption will be ignored, but leaving some fields written, which could lead to inconsistency or access uninitialized data. Explicitly reset the fields that could have been modified in case of unexpected size.

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 19:17 UTC

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6666 records in the last 180 days details

References

8 references

URL	Tags
https://git.kernel.org/stable/c/15e35fdad7a5576bf…
https://git.kernel.org/stable/c/b1256090816ec4601…
https://git.kernel.org/stable/c/192878df582c51d44…
https://git.kernel.org/stable/c/26dac5c9ffb20812b…
https://git.kernel.org/stable/c/4e80eff5c1c893aca…
https://git.kernel.org/stable/c/1fade1b2ac5b1a494…
https://git.kernel.org/stable/c/27ed642a4e7e4b5df…
https://git.kernel.org/stable/c/35772b4981f38ba80…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 648ef4b88673dadb8463bf0d4b10fbf33d55def8 , < 15e35fdad7a5576bf3f1c8d688877aeb5d1b506b (git) Affected: 648ef4b88673dadb8463bf0d4b10fbf33d55def8 , < b1256090816ec46011601e084be580731df58fc7 (git) Affected: 648ef4b88673dadb8463bf0d4b10fbf33d55def8 , < 192878df582c51d440bf7b91a15f297f29f2b596 (git) Affected: 648ef4b88673dadb8463bf0d4b10fbf33d55def8 , < 26dac5c9ffb20812b475fdf253eb04fab99cff3b (git) Affected: 648ef4b88673dadb8463bf0d4b10fbf33d55def8 , < 4e80eff5c1c893aca2ac1d202f0b256d2e52ecde (git) Affected: 648ef4b88673dadb8463bf0d4b10fbf33d55def8 , < 1fade1b2ac5b1a4948e538fae7313bea57b5ac36 (git) Affected: 648ef4b88673dadb8463bf0d4b10fbf33d55def8 , < 27ed642a4e7e4b5df4b8522c72c457a67e052493 (git) Affected: 648ef4b88673dadb8463bf0d4b10fbf33d55def8 , < 35772b4981f38ba8059372cde8753e8e477e98ec (git)
Linux	Linux	Affected: 5.6 Unaffected: 0 , < 5.6 (semver) Unaffected: 5.10.266 , ≤ 5.10.* (semver) Unaffected: 5.15.217 , ≤ 5.15.* (semver) Unaffected: 6.1.184 , ≤ 6.1.* (semver) Unaffected: 6.6.153 , ≤ 6.6.* (semver) Unaffected: 6.12.105 , ≤ 6.12.* (semver) Unaffected: 6.18.46 , ≤ 6.18.* (semver) Unaffected: 7.1.10 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

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{
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                "id": "CVE-2026-80586",
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                "role": "CISA Coordinator",
                "timestamp": "2026-10-16T19:17:59.284912Z",
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Sightings

Author	Source	Type	Date	Other

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.

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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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