{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "ac7b848390036dadd4351899d2a23748075916bd"
            },
            {
              "fixed": "5cf28d5c8dcbbe8af6d3b145babe491906d7bad1"
            },
            {
              "fixed": "504ba4168466c91210c45acdc332479cfd5f2da6"
            },
            {
              "fixed": "dc1739eff48e34cc71d4e2f03715493fbcebd8af"
            },
            {
              "fixed": "2cf2737c85a2ba2b52024dafe68ffad2676f97be"
            },
            {
              "fixed": "2c16e4d64dd91227742dfe196a3e7b0568bef65a"
            },
            {
              "fixed": "620f3d14c1ef51d425060a3056ad8dbae8f998a3"
            },
            {
              "fixed": "90bd7e8501349db3006d21fbc09df9ffcb172965"
            },
            {
              "fixed": "a242a9ae58aa46ff7dae51ce64150a93957abe65"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.14.0"
            },
            {
              "fixed": "5.10.253"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.203"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.168"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.134"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.81"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.22"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.12"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43027.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack_helper: pass helper to expect cleanup\n\nnf_conntrack_helper_unregister() calls nf_ct_expect_iterate_destroy()\nto remove expectations belonging to the helper being unregistered.\nHowever, it passes NULL instead of the helper pointer as the data\nargument, so expect_iter_me() never matches any expectation and all\nof them survive the cleanup.\n\nAfter unregister returns, nfnl_cthelper_del() frees the helper\nobject immediately.  Subsequent expectation dumps or packet-driven\ninit_conntrack() calls then dereference the freed exp-\u003ehelper,\ncausing a use-after-free.\n\nPass the actual helper pointer so expectations referencing it are\nproperly destroyed before the helper object is freed.\n\n  BUG: KASAN: slab-use-after-free in string+0x38f/0x430\n  Read of size 1 at addr ffff888003b14d20 by task poc/103\n  Call Trace:\n   string+0x38f/0x430\n   vsnprintf+0x3cc/0x1170\n   seq_printf+0x17a/0x240\n   exp_seq_show+0x2e5/0x560\n   seq_read_iter+0x419/0x1280\n   proc_reg_read+0x1ac/0x270\n   vfs_read+0x179/0x930\n   ksys_read+0xef/0x1c0\n  Freed by task 103:\n  The buggy address is located 32 bytes inside of\n   freed 192-byte region [ffff888003b14d00, ffff888003b14dc0)",
  "id": "CVE-2026-43027",
  "modified": "2026-07-08T05:38:02.350746800Z",
  "published": "2026-05-01T14:15:28.521Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2c16e4d64dd91227742dfe196a3e7b0568bef65a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2cf2737c85a2ba2b52024dafe68ffad2676f97be"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/504ba4168466c91210c45acdc332479cfd5f2da6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5cf28d5c8dcbbe8af6d3b145babe491906d7bad1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/620f3d14c1ef51d425060a3056ad8dbae8f998a3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/90bd7e8501349db3006d21fbc09df9ffcb172965"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a242a9ae58aa46ff7dae51ce64150a93957abe65"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/dc1739eff48e34cc71d4e2f03715493fbcebd8af"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43027.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43027"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "summary": "netfilter: nf_conntrack_helper: pass helper to expect cleanup"
}