FKIE_CVE-2026-31684

Vulnerability from fkie_nvd - Published: 2026-04-25 09:16 - Updated: 2026-06-17 10:34
Severity
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: net: sched: act_csum: validate nested VLAN headers tcf_csum_act() walks nested VLAN headers directly from skb->data when an skb still carries in-payload VLAN tags. The current code reads vlan->h_vlan_encapsulated_proto and then pulls VLAN_HLEN bytes without first ensuring that the full VLAN header is present in the linear area. If only part of an inner VLAN header is linearized, accessing h_vlan_encapsulated_proto reads past the linear area, and the following skb_pull(VLAN_HLEN) may violate skb invariants. Fix this by requiring pskb_may_pull(skb, VLAN_HLEN) before accessing and pulling each nested VLAN header. If the header still is not fully available, drop the packet through the existing error path.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/0410c619e86551677fb79887a38eccad3f5a0725
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3d165d975305cf76ff0b10a3c798fb31e5f5f9a5Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/46c07ad50fa2f4ba7663ee1b72b75ad7ad45cf09
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/886469b6455611a511aa6013e957e15e50577513
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a69738efea0996d05a3c7d2178551b891744df1bPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c842743d073bdd683606cb414eb0ca84465dd834Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/eb3765b90eb8f2a3d6310a80c14a9e57ec4267a2Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ec4930979b3f7bbeb7af5744599fc6603a4dba62Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel 7.0
linux linux_kernel 7.0
linux linux_kernel 7.0
linux linux_kernel 7.0
linux linux_kernel 7.0
linux linux_kernel 7.0
linux linux_kernel 7.0
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/sched/act_csum.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "0410c619e86551677fb79887a38eccad3f5a0725",
              "status": "affected",
              "version": "2ecba2d1e45b24620a7c3df9531895cf68d5dec6",
              "versionType": "git"
            },
            {
              "lessThan": "886469b6455611a511aa6013e957e15e50577513",
              "status": "affected",
              "version": "2ecba2d1e45b24620a7c3df9531895cf68d5dec6",
              "versionType": "git"
            },
            {
              "lessThan": "46c07ad50fa2f4ba7663ee1b72b75ad7ad45cf09",
              "status": "affected",
              "version": "2ecba2d1e45b24620a7c3df9531895cf68d5dec6",
              "versionType": "git"
            },
            {
              "lessThan": "eb3765b90eb8f2a3d6310a80c14a9e57ec4267a2",
              "status": "affected",
              "version": "2ecba2d1e45b24620a7c3df9531895cf68d5dec6",
              "versionType": "git"
            },
            {
              "lessThan": "a69738efea0996d05a3c7d2178551b891744df1b",
              "status": "affected",
              "version": "2ecba2d1e45b24620a7c3df9531895cf68d5dec6",
              "versionType": "git"
            },
            {
              "lessThan": "ec4930979b3f7bbeb7af5744599fc6603a4dba62",
              "status": "affected",
              "version": "2ecba2d1e45b24620a7c3df9531895cf68d5dec6",
              "versionType": "git"
            },
            {
              "lessThan": "3d165d975305cf76ff0b10a3c798fb31e5f5f9a5",
              "status": "affected",
              "version": "2ecba2d1e45b24620a7c3df9531895cf68d5dec6",
              "versionType": "git"
            },
            {
              "lessThan": "c842743d073bdd683606cb414eb0ca84465dd834",
              "status": "affected",
              "version": "2ecba2d1e45b24620a7c3df9531895cf68d5dec6",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3764bfae5056e95617b6ee074129297e11710886",
              "versionType": "git"
            },
            {
              "lessThan": "4.20",
              "status": "affected",
              "version": "4.19.99",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/sched/act_csum.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.1"
            },
            {
              "lessThan": "5.1",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.258",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.209",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.175",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.136",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.83",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.24",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.14",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "97340910-B0B6-42CC-B4FA-E277DFB61C71",
              "versionEndExcluding": "4.20",
              "versionStartIncluding": "4.19.99",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "B28CAC2A-4B06-4D07-8736-82E515099010",
              "versionEndExcluding": "6.6.136",
              "versionStartIncluding": "5.1",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "7F0AE5B5-23AC-4DCC-B37A-51CA1DAE7BA8",
              "versionEndExcluding": "6.12.83",
              "versionStartIncluding": "6.7",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "8126B8B8-6D0B-4443-86C1-672AEE893555",
              "versionEndExcluding": "6.18.24",
              "versionStartIncluding": "6.13",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "D6A8A074-BBF4-4803-ABED-519A839435BB",
              "versionEndExcluding": "6.19.14",
              "versionStartIncluding": "6.19",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*",
              "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*",
              "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*",
              "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*",
              "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*",
              "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*",
              "matchCriteriaId": "512EE3A8-A590-4501-9A94-5D4B268D6138",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: sched: act_csum: validate nested VLAN headers\n\ntcf_csum_act() walks nested VLAN headers directly from skb-\u003edata when an\nskb still carries in-payload VLAN tags. The current code reads\nvlan-\u003eh_vlan_encapsulated_proto and then pulls VLAN_HLEN bytes without\nfirst ensuring that the full VLAN header is present in the linear area.\n\nIf only part of an inner VLAN header is linearized, accessing\nh_vlan_encapsulated_proto reads past the linear area, and the following\nskb_pull(VLAN_HLEN) may violate skb invariants.\n\nFix this by requiring pskb_may_pull(skb, VLAN_HLEN) before accessing and\npulling each nested VLAN header. If the header still is not fully\navailable, drop the packet through the existing error path."
    }
  ],
  "id": "CVE-2026-31684",
  "lastModified": "2026-06-17T10:34:14.063",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2026-04-25T09:16:02.163",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0410c619e86551677fb79887a38eccad3f5a0725"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/3d165d975305cf76ff0b10a3c798fb31e5f5f9a5"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/46c07ad50fa2f4ba7663ee1b72b75ad7ad45cf09"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/886469b6455611a511aa6013e957e15e50577513"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/a69738efea0996d05a3c7d2178551b891744df1b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/c842743d073bdd683606cb414eb0ca84465dd834"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/eb3765b90eb8f2a3d6310a80c14a9e57ec4267a2"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/ec4930979b3f7bbeb7af5744599fc6603a4dba62"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}


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.