{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-43026","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-05-01T14:12:55.976Z","datePublished":"2026-05-01T14:15:27.854Z","dateUpdated":"2026-09-08T08:48:26.219Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T22:16:16.846Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ctnetlink: zero expect NAT fields when CTA_EXPECT_NAT absent\n\nctnetlink_alloc_expect() allocates expectations from a non-zeroing\nslab cache via nf_ct_expect_alloc().  When CTA_EXPECT_NAT is not\npresent in the netlink message, saved_addr and saved_proto are\nnever initialized.  Stale data from a previous slab occupant can\nthen be dumped to userspace by ctnetlink_exp_dump_expect(), which\nchecks these fields to decide whether to emit CTA_EXPECT_NAT.\n\nThe safe sibling nf_ct_expect_init(), used by the packet path,\nexplicitly zeroes these fields.\n\nZero saved_addr, saved_proto and dir in the else branch, guarded\nby IS_ENABLED(CONFIG_NF_NAT) since these fields only exist when\nNAT is enabled.\n\nConfirmed by priming the expect slab with NAT-bearing expectations,\nfreeing them, creating a new expectation without CTA_EXPECT_NAT,\nand observing that the ctnetlink dump emits a spurious\nCTA_EXPECT_NAT containing stale data from the prior allocation."}],"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_netlink.c"],"versions":[{"version":"076a0ca02644657b13e4af363f487ced2942e9cb","lessThan":"a5a89db6981a1ddf2314bf50cb49db5a3146185f","status":"affected","versionType":"git"},{"version":"076a0ca02644657b13e4af363f487ced2942e9cb","lessThan":"1c2ebdeff8d088a2e47ae25d7b38447249adace2","status":"affected","versionType":"git"},{"version":"076a0ca02644657b13e4af363f487ced2942e9cb","lessThan":"a64b7bf84b4d5ea54218c5d374ec87fff9000f43","status":"affected","versionType":"git"},{"version":"076a0ca02644657b13e4af363f487ced2942e9cb","lessThan":"2898080c054ea4d6ddfaaf21bbedbc229a9a8376","status":"affected","versionType":"git"},{"version":"076a0ca02644657b13e4af363f487ced2942e9cb","lessThan":"fd002ff2ea030cbfb0188a11b3c60ce7f84485f4","status":"affected","versionType":"git"},{"version":"076a0ca02644657b13e4af363f487ced2942e9cb","lessThan":"929f7a9a7aad9404a5867216c3f8738232355b38","status":"affected","versionType":"git"},{"version":"076a0ca02644657b13e4af363f487ced2942e9cb","lessThan":"bff0f4f06f12d6d9bc565a3e1378abd4f6f5ce36","status":"affected","versionType":"git"},{"version":"076a0ca02644657b13e4af363f487ced2942e9cb","lessThan":"35177c6877134a21315f37d57a5577846225623e","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_netlink.c"],"versions":[{"version":"3.4","status":"affected"},{"version":"0","lessThan":"3.4","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":"3.4","versionEndExcluding":"5.10.253"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"5.15.203"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"6.1.168"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"6.6.134"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"6.12.81"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"6.18.22"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"6.19.12"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"7.0"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/a5a89db6981a1ddf2314bf50cb49db5a3146185f"},{"url":"https://git.kernel.org/stable/c/1c2ebdeff8d088a2e47ae25d7b38447249adace2"},{"url":"https://git.kernel.org/stable/c/a64b7bf84b4d5ea54218c5d374ec87fff9000f43"},{"url":"https://git.kernel.org/stable/c/2898080c054ea4d6ddfaaf21bbedbc229a9a8376"},{"url":"https://git.kernel.org/stable/c/fd002ff2ea030cbfb0188a11b3c60ce7f84485f4"},{"url":"https://git.kernel.org/stable/c/929f7a9a7aad9404a5867216c3f8738232355b38"},{"url":"https://git.kernel.org/stable/c/bff0f4f06f12d6d9bc565a3e1378abd4f6f5ce36"},{"url":"https://git.kernel.org/stable/c/35177c6877134a21315f37d57a5577846225623e"}],"title":"netfilter: ctnetlink: zero expect NAT fields when CTA_EXPECT_NAT absent","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"x_adpType":"supplier","providerMetadata":{"orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","shortName":"siemens-SADP","dateUpdated":"2026-09-08T08:48:26.219Z"},"affected":[{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","versions":[{"status":"affected","version":"V3.1.6","lessThan":"*","versionType":"custom"}],"defaultStatus":"unknown"},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","versions":[{"status":"affected","version":"V3.1.5","lessThan":"*","versionType":"custom"}],"defaultStatus":"unknown"},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","versions":[{"status":"affected","version":"V3.1.6","lessThan":"*","versionType":"custom"}],"defaultStatus":"unknown"},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP 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