{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "d0c081b49137cd3200f2023c0875723be66e7ce5"
            },
            {
              "fixed": "3f6000fdf8a57b9786669869af8a3e050b541bf3"
            },
            {
              "fixed": "2c2f82b696c5e877f60ea77b7784e906a5e63014"
            },
            {
              "fixed": "d44e66f5dd99319a32e378b610af7fcf78da985a"
            },
            {
              "fixed": "d9e08836d06c84abb18470c94b12b131eaccdc7d"
            },
            {
              "fixed": "50d0cd575cab763f833d6ac6eb6550b23a0b3dae"
            },
            {
              "fixed": "9993e6a0ac1b5b3101ffba702cacb9f42b9909d8"
            },
            {
              "fixed": "52efce4755a4b8b82039caa773645ffc80b25362"
            },
            {
              "fixed": "99bda1ecbd56905f8bd934b9cdccd3bd251192b1"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "4.4.114"
            },
            {
              "fixed": "4.5"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "4.9.79"
            },
            {
              "fixed": "4.10"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "4.14.16"
            },
            {
              "fixed": "4.15"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "d35cd5e279881ec36ff8cd82a2d9caebc0cce3fc"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "eecfa2eeefe3caef4c8d6b2284f6066c76ab26a1"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "80f327285cab6ab8e10c3ea03278add5dd99fb02"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.15.0"
            },
            {
              "fixed": "5.10.273"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.224"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.191"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.160"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.113"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.57"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.11"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98955.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nflow_dissector: avoid u16 truncation of skb-\u003elen when computing thoff\n\n__skb_flow_dissect() computes key_control-\u003ethoff using:\n\n  key_control-\u003ethoff = min_t(u16, nhoff, skb ? skb-\u003elen : hlen);\n\nmin_t(u16, ...) casts both arguments to u16 before comparing them.\nWhenever skb-\u003elen (or hlen) modulo 65536 is smaller than nhoff, the\ntruncated length wins and thoff is set to a bogus small value, even\nwhen the dissection succeeded. For example, an IPv4/TCP frame with\nskb-\u003elen == 65540 and nhoff == 34 gets thoff == 4, so callers such as\nskb_probe_transport_header() point the transport header inside the\nEthernet header.\n\nSuch skbs are not exotic:\n- At the time of commit d0c081b49137 (\"flow_dissector: properly cap\n  thoff field\"), AF_PACKET with PACKET_VNET_HDR could already build GSO\n  skbs larger than 64KB (MTU checks are skipped for GSO, and\n  alloc_skb_with_frags() accepted up to MAX_SKB_FRAGS (17) order-0\n  pages on top of the linear part).\n- BIG TCP now makes skbs larger than 64KB common.\n- The following patch makes tun_get_user() dissect IFF_TAP frames\n  before eth_type_trans() pulls the Ethernet header, so a GSO frame\n  carrying a 65522..65535 byte L3 packet will be dissected with\n  skb-\u003elen in [65536, 65549].\n\nCompare as u32 instead. If the resulting offset cannot be represented\nin the u16 key_control-\u003ethoff, cap it to U16_MAX and report the\ndissection as failed rather than silently returning a wrong transport\noffset. thoff is still set on failure, as some callers (such as\neth_get_headlen()) use it regardless of the return value.",
  "id": "CVE-2026-98955",
  "modified": "2026-11-01T02:30:27.775274909Z",
  "published": "2026-10-23T12:19:15.287Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2c2f82b696c5e877f60ea77b7784e906a5e63014"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3f6000fdf8a57b9786669869af8a3e050b541bf3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/50d0cd575cab763f833d6ac6eb6550b23a0b3dae"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/52efce4755a4b8b82039caa773645ffc80b25362"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9993e6a0ac1b5b3101ffba702cacb9f42b9909d8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/99bda1ecbd56905f8bd934b9cdccd3bd251192b1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d44e66f5dd99319a32e378b610af7fcf78da985a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d9e08836d06c84abb18470c94b12b131eaccdc7d"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98955.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98955"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.2",
  "summary": "flow_dissector: avoid u16 truncation of skb-\u003elen when computing thoff"
}