{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "9a05475cebdd6341884b5901e53870be26e65158"
            },
            {
              "fixed": "3bf9a260188b2a5449cbddc032a749ab433fe328"
            },
            {
              "fixed": "6378c5cb360eb1750f88839d7c3613ea92ac1816"
            },
            {
              "fixed": "32c299e28b8eea6cbbd23b97dc61401e9ef9c445"
            },
            {
              "fixed": "9e36602cbec552286f7e691cfd366525c565ee74"
            },
            {
              "fixed": "d0eed7177e822cab83141e5c44b2aa345c7fd379"
            },
            {
              "fixed": "83fb4c2c5344f02eac929f66de3c9d1adfcde04c"
            },
            {
              "fixed": "6335ab62d5fc9ed875279238233fba3462c168f5"
            },
            {
              "fixed": "2975324d164c552b028632f107b567302863b7f6"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.10.0"
            },
            {
              "fixed": "5.10.261"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.212"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.178"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.145"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.97"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.40"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72020.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nipvs: reset full ip_vs_seq structs in ip_vs_conn_new\n\nCommit 9a05475cebdd (\"ipvs: avoid kmem_cache_zalloc in\nip_vs_conn_new\") changed ip_vs_conn_new() to allocate an ip_vs_conn\nobject with kmem_cache_alloc().  The function then initializes many\nfields explicitly, but only resets in_seq.delta and out_seq.delta in the\ntwo struct ip_vs_seq members.\n\nThat leaves init_seq and previous_delta uninitialized.  This is normally\nharmless while the corresponding IP_VS_CONN_F_IN_SEQ or\nIP_VS_CONN_F_OUT_SEQ flag is clear.  For connections learned from a sync\nmessage, however, ip_vs_proc_conn() preserves those flags from\nIP_VS_CONN_F_BACKUP_MASK and passes opt=NULL when the message omits\nIPVS_OPT_SEQ_DATA.  In that case the new connection can be hashed with\nSEQ flags set but with the rest of in_seq/out_seq still containing stale\nslab data.\n\nWhen a packet for such a connection is later handled by an IPVS\napplication helper, vs_fix_seq() and vs_fix_ack_seq() use\nprevious_delta and init_seq to rewrite TCP sequence numbers.  A malformed\nsync message can therefore make forwarded packets carry stale slab bytes\nin their TCP seq/ack numbers, and can also corrupt the forwarded TCP\nflow.\n\nReset both struct ip_vs_seq members completely before publishing the\nconnection.  This matches the existing \"reset struct ip_vs_seq\" comment\nand keeps the sequence-adjustment gates inactive unless valid sequence\ndata is installed later.",
  "id": "CVE-2026-72020",
  "modified": "2026-08-16T03:31:25.208028668Z",
  "published": "2026-08-15T05:51:46.675Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2975324d164c552b028632f107b567302863b7f6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/32c299e28b8eea6cbbd23b97dc61401e9ef9c445"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3bf9a260188b2a5449cbddc032a749ab433fe328"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6335ab62d5fc9ed875279238233fba3462c168f5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6378c5cb360eb1750f88839d7c3613ea92ac1816"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/83fb4c2c5344f02eac929f66de3c9d1adfcde04c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9e36602cbec552286f7e691cfd366525c565ee74"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d0eed7177e822cab83141e5c44b2aa345c7fd379"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72020.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72020"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "ipvs: reset full ip_vs_seq structs in ip_vs_conn_new"
}