{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2023-52927","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-08-21T06:07:11.018Z","datePublished":"2025-03-14T14:25:59.166Z","dateUpdated":"2026-08-05T09:12:05.687Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T09:12:05.687Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: allow exp not to be removed in nf_ct_find_expectation\n\nCurrently nf_conntrack_in() calling nf_ct_find_expectation() will\nremove the exp from the hash table. However, in some scenario, we\nexpect the exp not to be removed when the created ct will not be\nconfirmed, like in OVS and TC conntrack in the following patches.\n\nThis patch allows exp not to be removed by setting IPS_CONFIRMED\nin the status of the tmpl."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - Exploitation requires local nftables/netlink configuration and locally generated packets (e.g. loopback) to drive nft_ct_set_zone_eval and nf_nat_setup_info; it is not reachable from unauthenticated remote packet processing alone.\nAC:L - The attacker fully controls both sides of the trigger by installing nftables rules (ct zone + NAT) and sending packets, then freeing the template while it remains linked; no victim state or uncontrolled race is required.\nPR:L - nftables setup needs CAP_NET_ADMIN, which an unprivileged user can obtain in a user+network namespace (unshare -Urn); real init-namespace root is not required.\nUI:N - No victim action is needed; the attacker configures netfilter rules and sends their own packets to trigger the UAF.\nS:U - Impact is privilege escalation within the same kernel/host security authority (standard local LPE), not a VM/IOMMU/sandbox boundary cross.\nC:H - The free-without-unlink UAF write into nf_nat_bysource enables reclaim of the freed kmalloc-256 object and arbitrary kernel read primitives, as demonstrated in the public LPE exploit.\nI:H - The same UAF primitive was exploited for RIP control and local privilege escalation via controlled kernel writes and expression ops overwrite.\nA:H - Use-after-free on the nf_nat_bysource hlist causes kernel oops/panic even without full exploitation, and successful LPE trivially yields denial of service."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/net/netfilter/nf_conntrack_expect.h","net/netfilter/nf_conntrack_core.c","net/netfilter/nf_conntrack_expect.c","net/netfilter/nft_ct.c"],"versions":[{"version":"1bc91a5ddf3eaea0e0ea957cccf3abdcfcace00e","lessThan":"3fa58a6fbd1e9e5682d09cdafb08fba004cb12ec","status":"affected","versionType":"git"},{"version":"1bc91a5ddf3eaea0e0ea957cccf3abdcfcace00e","lessThan":"4914109a8e1e494c6aa9852f9e84ec77a5fc643f","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/net/netfilter/nf_conntrack_expect.h","net/netfilter/nf_conntrack_core.c","net/netfilter/nf_conntrack_expect.c","net/netfilter/nft_ct.c"],"versions":[{"version":"5.18","status":"affected"},{"version":"0","lessThan":"5.18","status":"unaffected","versionType":"semver"},{"version":"6.1.130","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6","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":"5.18","versionEndExcluding":"6.1.130"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.18","versionEndExcluding":"6.6"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/3fa58a6fbd1e9e5682d09cdafb08fba004cb12ec"},{"url":"https://git.kernel.org/stable/c/4914109a8e1e494c6aa9852f9e84ec77a5fc643f"},{"url":"https://seadragnol.github.io/posts/CVE-2023-52927/"}],"title":"netfilter: allow exp not to be removed in nf_ct_find_expectation","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2025-11-03T19:28:52.085Z"}},{"x_adpType":"supplier","providerMetadata":{"orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","shortName":"siemens-SADP","dateUpdated":"2026-07-14T12:33:30.489Z"},"affected":[{"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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