CVE-2026-80844 (GCVE-0-2026-80844)

Vulnerability from cvelistv5 – Published: 2026-09-04 15:54 – Updated: 2026-09-04 15:54
VLAI
Title
xfrm: ah6: validate routing header segments_left
Summary
In the Linux kernel, the following vulnerability has been resolved: xfrm: ah6: validate routing header segments_left AH6 rearranges routing-header addresses before computing or verifying the ICV. ipv6_rearrange_rthdr() assumes that segments_left is not larger than the number of addresses described by the routing header's hdrlen field. That assumption does not hold for raw IPv6 HDRINCL packets. A packet with hdrlen equal to 2 describes one address, but can carry an arbitrary segments_left value. With segments_left equal to 255, the function moves its address pointer 4,064 bytes backwards and passes a 4,064-byte length to memmove(), resulting in an out-of-bounds access. Validate the invariant locally before modifying the routing header or performing any address-pointer arithmetic, and propagate malformed-header errors to the existing AH6 input and output error paths.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 2dc650956e4e163b879b3fb1027f9557abc5c985 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 48b0e36cf54358276ee7aa897034c973097d2bc9 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 1b7e066eabcc7d6d8f476c34739b45932f2f4c31 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < f00df8500e5a36ba70d336fd34bd2152ea074e5f (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 1516e31ac458a738be485620579d8f7fb2700fcb (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 6733ae71268a27d598cfb3f3339a3c950b9b656d (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 0bf11081ad3753938a2b48723ce6298dbac743a1 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 46640c814f25f096b0b0045ca50e1b7030cd8a30 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 7bad4bda74dc4713f398d3b7624ff05478e3a568 (git)
Create a notification for this product.
Linux Linux Affected: 2.6.12
Unaffected: 0 , < 2.6.12 (semver)
Unaffected: 5.10.269 , ≤ 5.10.* (semver)
Unaffected: 5.15.220 , ≤ 5.15.* (semver)
Unaffected: 6.1.187 , ≤ 6.1.* (semver)
Unaffected: 6.6.156 , ≤ 6.6.* (semver)
Unaffected: 6.12.108 , ≤ 6.12.* (semver)
Unaffected: 6.18.49 , ≤ 6.18.* (semver)
Unaffected: 7.1.13 , ≤ 7.1.* (semver)
Unaffected: 7.2.3 , ≤ 7.2.* (semver)
Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)
Create a notification for this product.
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        }
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          }
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        "id": "CVE-2026-80844",
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        "metrics": {},
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        "vulnStatus": "Received"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Important",
      "current_release_date": "2026-09-30T17:07:35+00:00",
      "cve": "CVE-2026-80844",
      "id": "CVE-2026-80844",
      "initial_release_date": "2026-09-04T00:00:00+00:00",
      "product_status:fixed": "2283",
      "product_status:known_affected": "25",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: xfrm: ah6: validate routing header segments_left",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80844.json",
      "version": "3"
    }
  }
}



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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.