{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "2ecba2d1e45b24620a7c3df9531895cf68d5dec6"
            },
            {
              "fixed": "0410c619e86551677fb79887a38eccad3f5a0725"
            },
            {
              "fixed": "886469b6455611a511aa6013e957e15e50577513"
            },
            {
              "fixed": "46c07ad50fa2f4ba7663ee1b72b75ad7ad45cf09"
            },
            {
              "fixed": "eb3765b90eb8f2a3d6310a80c14a9e57ec4267a2"
            },
            {
              "fixed": "a69738efea0996d05a3c7d2178551b891744df1b"
            },
            {
              "fixed": "ec4930979b3f7bbeb7af5744599fc6603a4dba62"
            },
            {
              "fixed": "3d165d975305cf76ff0b10a3c798fb31e5f5f9a5"
            },
            {
              "fixed": "c842743d073bdd683606cb414eb0ca84465dd834"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "3764bfae5056e95617b6ee074129297e11710886"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "4.19.99"
            },
            {
              "fixed": "4.20"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.1.0"
            },
            {
              "fixed": "5.10.258"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.209"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.175"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.136"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.83"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.24"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.14"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31684.json"
  },
  "details": "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",
  "modified": "2026-07-08T05:36:25.324347364Z",
  "published": "2026-04-25T08:47:01.555Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0410c619e86551677fb79887a38eccad3f5a0725"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3d165d975305cf76ff0b10a3c798fb31e5f5f9a5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/46c07ad50fa2f4ba7663ee1b72b75ad7ad45cf09"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/886469b6455611a511aa6013e957e15e50577513"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a69738efea0996d05a3c7d2178551b891744df1b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c842743d073bdd683606cb414eb0ca84465dd834"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/eb3765b90eb8f2a3d6310a80c14a9e57ec4267a2"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ec4930979b3f7bbeb7af5744599fc6603a4dba62"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31684.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31684"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "summary": "net: sched: act_csum: validate nested VLAN headers"
}