{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "10d3be569243def8d92ac3722395ef5a59c504e6"
            },
            {
              "fixed": "8eb51013b6308870479a64b4a2a018697b997849"
            },
            {
              "fixed": "711bfd762bec05fb19bc3b17cbb157c39f4e66da"
            },
            {
              "fixed": "3d4e005c198dc410ad568f832bffa7569c059ff8"
            },
            {
              "fixed": "4fd2ee4ac154c204d95d8db72221446dac5af9b8"
            },
            {
              "fixed": "ebe55406404f3cb28e36d2b668e2c6c05026ec29"
            },
            {
              "fixed": "b8f08a94b2a4addc39249dcf9c792e786108621b"
            },
            {
              "fixed": "47eb90299e6882d6445672530dd7c51ac33ebdbd"
            },
            {
              "fixed": "ce2b807f42ed5e55567b8864ab72963f90779270"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.7.0"
            },
            {
              "fixed": "5.10.270"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.221"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.188"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.157"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.110"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.52"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90054.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: fix corruption of urgent data on multi-segment retransmit\n\nOn the normal xmit path, while in urgent mode we refuse to build a\nmulti-segment TSO packet, so every segment gets its own urg_ptr:\n\n\t/* tcp_write_xmit() */\n\tlimit = mss_now;\n\tif (tso_segs \u003e 1 \u0026\u0026 !tcp_urg_mode(tp))\n\t\tlimit = tcp_mss_split_point(...);\n\nThe retransmit path has no such guard. __tcp_retransmit_skb() builds a\nsegs \u003e 1 skb and hands it to the GSO layer, which only advances th-\u003eseq\nper segment and copies urg_ptr verbatim:\n\n\t/* __tcp_retransmit_skb() */\n\tlen = cur_mss * segs;\t\t/* segs \u003e 1, no urg_mode check */\n\t...\n\t/* tcp_gso_segment(): bumps seq only, urg_ptr is copied */\n\nurg_ptr is an offset from the segment's own seq, so a copied value points\nat a different place on each segment. The receiver rebuilds the absolute\nurgent seq as seg.seq + urg_ptr, so it walks a moving urgent point instead\nof the one OOB byte:\n\n\tseg1  seq 1     urg_ptr 5001 -\u003e urgent @ 5001   (ok)\n\tseg2  seq 1001  urg_ptr 5001 -\u003e urgent @ 6001   (wrong, +MSS)\n\tseg3  seq 2001  urg_ptr 5001 -\u003e urgent @ 7001   (wrong, +2*MSS)\n\nThe real OOB byte is never pointed at, so the receiver stops splicing it\nout and delivers it as normal in-band data, corrupting the stream.\n\nGuard the retransmit length like the xmit path: keep segs = 1 while in\nurgent mode.",
  "id": "CVE-2026-90054",
  "modified": "2026-09-19T03:30:28.351227614Z",
  "published": "2026-09-17T16:05:39.632Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3d4e005c198dc410ad568f832bffa7569c059ff8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/47eb90299e6882d6445672530dd7c51ac33ebdbd"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4fd2ee4ac154c204d95d8db72221446dac5af9b8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/711bfd762bec05fb19bc3b17cbb157c39f4e66da"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8eb51013b6308870479a64b4a2a018697b997849"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b8f08a94b2a4addc39249dcf9c792e786108621b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ce2b807f42ed5e55567b8864ab72963f90779270"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ebe55406404f3cb28e36d2b668e2c6c05026ec29"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90054.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-90054"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "tcp: fix corruption of urgent data on multi-segment retransmit"
}