{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1"
            },
            {
              "fixed": "a16eaaf7c0b0ccdef6166707d90ffbc6eebf6855"
            },
            {
              "fixed": "fbfa3ad2ad6f3a5624aba5211c46290fb98cc9dc"
            },
            {
              "fixed": "100a23b1613e9218e0af654ef102352c713f0263"
            },
            {
              "fixed": "ea85dbcbe8d4056ecb54352f97743d138ea4c407"
            },
            {
              "fixed": "4032f8ed10fcb84d41c508dfb04be96589f78dfe"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.8.0"
            },
            {
              "fixed": "6.6.148"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.101"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.42"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68123.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nopenvswitch: fix GSO userspace truncation underflow\n\nOVS_ACTION_ATTR_TRUNC currently stores a delta from the original skb\nlength in OVS_CB(skb)-\u003ecutlen. When a later userspace action segments a\nGSO skb, queue_gso_packets() reuses that delta for each smaller segment.\nA segment can then reach queue_userspace_packet() with cutlen greater\nthan skb-\u003elen, underflowing the length passed to skb_zerocopy().\n\nStore the maximum preserved length instead and bound each consumer\nagainst the current skb length. Use U32_MAX as the no-truncation\nsentinel so the value remains valid if skb geometry changes before a\nconsumer handles it.",
  "id": "CVE-2026-68123",
  "modified": "2026-08-12T03:51:40.226055359Z",
  "published": "2026-08-10T11:58:43.727Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/100a23b1613e9218e0af654ef102352c713f0263"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4032f8ed10fcb84d41c508dfb04be96589f78dfe"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a16eaaf7c0b0ccdef6166707d90ffbc6eebf6855"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ea85dbcbe8d4056ecb54352f97743d138ea4c407"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fbfa3ad2ad6f3a5624aba5211c46290fb98cc9dc"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68123.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-68123"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "openvswitch: fix GSO userspace truncation underflow"
}