FKIE_CVE-2026-80731

Vulnerability from fkie_nvd - Published: 2026-09-03 13:06 - Updated: 2026-09-04 05:17
Severity
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: net: remove CAP_SYS_RAWIO zero-padding in dev_validate_header dev_validate_header() reads dev->hard_header_len directly when zero-padding short link layer headers for CAP_SYS_RAWIO holders: if (capable(CAP_SYS_RAWIO)) { memset(ll_header + len, 0, dev->hard_header_len - len); return true; } Packet send paths call dev_validate_header() on skbs whose headroom was allocated from an earlier hard_header_len read. If the device is reconfigured so that dev->hard_header_len increases before validation, the memset writes past the reserved buffer, an out-of-bounds write. This out-of-bounds write is masked in some SOCK_RAW paths today because the same concurrent increase can first make skb_push() exceed the reserved headroom and trigger skb_under_panic(). Remove the zero-padding branch before making those hard_header_len reads consistent, so the snapshot fixes do not turn a loud panic into a silent overwrite. This path is only reached for variable length L2 protocols, where len < hard_header_len but len >= min_header_len. No remaining in-tree variable length L2 protocol implements header_ops->validate, and the CAP_SYS_RAWIO bypass that zero-pads and accepts short headers has no real value beyond allowing testing of intentionally malformed input. Drop the CAP_SYS_RAWIO branch. The remaining reads of dev->hard_header_len in dev_validate_header() are comparisons only and have no memory safety impact.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3b9a324e646d3657a8d9806dfbfe4f3e4066e882
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/53fd7f912c0877647d6a1e1877f5ea8535ee0b4a
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/74e035f07f53feca09e2352e77fccb09cad5e208
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/8fc9816404166a90ed8d544dc52482fafffb6d9f
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/99df6b7a713f96eda206680d100b76e15f9d9b69
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/b0f92a5731dc82556a9ae005cc35f71ab136307b
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/dbb30dc943a93e083f1e531bfdc6779e57de40d0
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/fa6d98dd925e72fc028b26a0cbbff9d2f0601ff6
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/fc902f52a02298c7432b2334c0c82a2885a1a8b6
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "include/linux/netdevice.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "53fd7f912c0877647d6a1e1877f5ea8535ee0b4a",
              "status": "affected",
              "version": "b5518429e70cd783b8ca52335456172c1a0589f6",
              "versionType": "git"
            },
            {
              "lessThan": "fa6d98dd925e72fc028b26a0cbbff9d2f0601ff6",
              "status": "affected",
              "version": "2793a23aacbd754dbbb5cb75093deb7e4103bace",
              "versionType": "git"
            },
            {
              "lessThan": "8fc9816404166a90ed8d544dc52482fafffb6d9f",
              "status": "affected",
              "version": "2793a23aacbd754dbbb5cb75093deb7e4103bace",
              "versionType": "git"
            },
            {
              "lessThan": "b0f92a5731dc82556a9ae005cc35f71ab136307b",
              "status": "affected",
              "version": "2793a23aacbd754dbbb5cb75093deb7e4103bace",
              "versionType": "git"
            },
            {
              "lessThan": "99df6b7a713f96eda206680d100b76e15f9d9b69",
              "status": "affected",
              "version": "2793a23aacbd754dbbb5cb75093deb7e4103bace",
              "versionType": "git"
            },
            {
              "lessThan": "74e035f07f53feca09e2352e77fccb09cad5e208",
              "status": "affected",
              "version": "2793a23aacbd754dbbb5cb75093deb7e4103bace",
              "versionType": "git"
            },
            {
              "lessThan": "dbb30dc943a93e083f1e531bfdc6779e57de40d0",
              "status": "affected",
              "version": "2793a23aacbd754dbbb5cb75093deb7e4103bace",
              "versionType": "git"
            },
            {
              "lessThan": "fc902f52a02298c7432b2334c0c82a2885a1a8b6",
              "status": "affected",
              "version": "2793a23aacbd754dbbb5cb75093deb7e4103bace",
              "versionType": "git"
            },
            {
              "lessThan": "3b9a324e646d3657a8d9806dfbfe4f3e4066e882",
              "status": "affected",
              "version": "2793a23aacbd754dbbb5cb75093deb7e4103bace",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "f58a6c08ebdfa978178bbca78c2ba744a2665912",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1df16498dfd0d5a129bdf2982d9a08df73e8923d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "8b8d278aa4de9335682bbd4a3bb619af015c859e",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "6804052fa9d86e9a512c88b24a5debbfc1a490fc",
              "versionType": "git"
            },
            {
              "lessThan": "3.2.81",
              "status": "affected",
              "version": "3.2.80",
              "versionType": "semver"
            },
            {
              "lessThan": "3.17",
              "status": "affected",
              "version": "3.16.36",
              "versionType": "semver"
            },
            {
              "lessThan": "4.2",
              "status": "affected",
              "version": "4.1.28",
              "versionType": "semver"
            },
            {
              "lessThan": "4.5",
              "status": "affected",
              "version": "4.4.8",
              "versionType": "semver"
            },
            {
              "lessThan": "4.6",
              "status": "affected",
              "version": "4.5.2",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "include/linux/netdevice.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.6"
            },
            {
              "lessThan": "4.6",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "3.2.*",
              "status": "unaffected",
              "version": "3.2.81",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.265",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.216",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.183",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.152",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.104",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.45",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.9",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: remove CAP_SYS_RAWIO zero-padding in dev_validate_header\n\ndev_validate_header() reads dev-\u003ehard_header_len directly when\nzero-padding short link layer headers for CAP_SYS_RAWIO holders:\n\n    if (capable(CAP_SYS_RAWIO)) {\n        memset(ll_header + len, 0, dev-\u003ehard_header_len - len);\n        return true;\n    }\n\nPacket send paths call dev_validate_header() on skbs whose headroom was\nallocated from an earlier hard_header_len read. If the device is\nreconfigured so that dev-\u003ehard_header_len increases before validation,\nthe memset writes past the reserved buffer, an out-of-bounds write.\n\nThis out-of-bounds write is masked in some SOCK_RAW paths today because\nthe same concurrent increase can first make skb_push() exceed the\nreserved headroom and trigger skb_under_panic(). Remove the zero-padding\nbranch before making those hard_header_len reads consistent, so the\nsnapshot fixes do not turn a loud panic into a silent overwrite.\n\nThis path is only reached for variable length L2 protocols, where\nlen \u003c hard_header_len but len \u003e= min_header_len. No remaining in-tree\nvariable length L2 protocol implements header_ops-\u003evalidate, and the\nCAP_SYS_RAWIO bypass that zero-pads and accepts short headers has no\nreal value beyond allowing testing of intentionally malformed input.\n\nDrop the CAP_SYS_RAWIO branch. The remaining reads of\ndev-\u003ehard_header_len in dev_validate_header() are comparisons only and\nhave no memory safety impact."
    }
  ],
  "id": "CVE-2026-80731",
  "lastModified": "2026-09-04T05:17:13.583",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-09-03T13:06:11.707",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3b9a324e646d3657a8d9806dfbfe4f3e4066e882"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/53fd7f912c0877647d6a1e1877f5ea8535ee0b4a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/74e035f07f53feca09e2352e77fccb09cad5e208"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/8fc9816404166a90ed8d544dc52482fafffb6d9f"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/99df6b7a713f96eda206680d100b76e15f9d9b69"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/b0f92a5731dc82556a9ae005cc35f71ab136307b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/dbb30dc943a93e083f1e531bfdc6779e57de40d0"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/fa6d98dd925e72fc028b26a0cbbff9d2f0601ff6"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/fc902f52a02298c7432b2334c0c82a2885a1a8b6"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.


Detection rules are retrieved from Rulezet.


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.