{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-43027", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-01T14:12:55.976Z", "datePublished": "2026-05-01T14:15:28.521Z", "dateUpdated": "2026-05-11T22:16:18.081Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T22:16:18.081Z"}, "descriptions": [{"lang": "en", "value": "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->helper,\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)"}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/netfilter/nf_conntrack_helper.c"], "versions": [{"version": "ac7b848390036dadd4351899d2a23748075916bd", "lessThan": "5cf28d5c8dcbbe8af6d3b145babe491906d7bad1", "status": "affected", "versionType": "git"}, {"version": "ac7b848390036dadd4351899d2a23748075916bd", "lessThan": "504ba4168466c91210c45acdc332479cfd5f2da6", "status": "affected", "versionType": "git"}, {"version": "ac7b848390036dadd4351899d2a23748075916bd", "lessThan": "dc1739eff48e34cc71d4e2f03715493fbcebd8af", "status": "affected", "versionType": "git"}, {"version": "ac7b848390036dadd4351899d2a23748075916bd", "lessThan": "2cf2737c85a2ba2b52024dafe68ffad2676f97be", "status": "affected", "versionType": "git"}, {"version": "ac7b848390036dadd4351899d2a23748075916bd", "lessThan": "2c16e4d64dd91227742dfe196a3e7b0568bef65a", "status": "affected", "versionType": "git"}, {"version": "ac7b848390036dadd4351899d2a23748075916bd", "lessThan": "620f3d14c1ef51d425060a3056ad8dbae8f998a3", "status": "affected", "versionType": "git"}, {"version": "ac7b848390036dadd4351899d2a23748075916bd", "lessThan": "90bd7e8501349db3006d21fbc09df9ffcb172965", "status": "affected", "versionType": "git"}, {"version": "ac7b848390036dadd4351899d2a23748075916bd", "lessThan": "a242a9ae58aa46ff7dae51ce64150a93957abe65", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/netfilter/nf_conntrack_helper.c"], "versions": [{"version": "4.14", "status": "affected"}, {"version": "0", "lessThan": "4.14", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.253", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.203", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.168", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.134", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.81", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.22", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19.12", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "5.10.253"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "5.15.203"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "6.1.168"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "6.6.134"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "6.12.81"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "6.18.22"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "6.19.12"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "7.0"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/5cf28d5c8dcbbe8af6d3b145babe491906d7bad1"}, {"url": "https://git.kernel.org/stable/c/504ba4168466c91210c45acdc332479cfd5f2da6"}, {"url": "https://git.kernel.org/stable/c/dc1739eff48e34cc71d4e2f03715493fbcebd8af"}, {"url": "https://git.kernel.org/stable/c/2cf2737c85a2ba2b52024dafe68ffad2676f97be"}, {"url": "https://git.kernel.org/stable/c/2c16e4d64dd91227742dfe196a3e7b0568bef65a"}, {"url": "https://git.kernel.org/stable/c/620f3d14c1ef51d425060a3056ad8dbae8f998a3"}, {"url": "https://git.kernel.org/stable/c/90bd7e8501349db3006d21fbc09df9ffcb172965"}, {"url": "https://git.kernel.org/stable/c/a242a9ae58aa46ff7dae51ce64150a93957abe65"}], "title": "netfilter: nf_conntrack_helper: pass helper to expect cleanup", "x_generator": {"engine": "bippy-1.2.0"}}}}