{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-40168", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:20:57.176Z", "datePublished": "2025-11-12T10:46:51.422Z", "dateUpdated": "2026-09-02T12:49:28.040Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-09-02T12:49:28.040Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmc: Use __sk_dst_get() and dst_dev_rcu() in smc_clc_prfx_match().\n\nsmc_clc_prfx_match() is called from smc_listen_work() and\nnot under RCU nor RTNL.\n\nUsing sk_dst_get(sk)->dev could trigger UAF.\n\nLet's use __sk_dst_get() and dst_dev_rcu().\n\nNote that the returned value of smc_clc_prfx_match() is not\nused in the caller." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.1, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - The vulnerable read is performed by the SMC listen worker while parsing a CLC Proposal message received over TCP from a remote peer (smc_listen_work → smc_listen_find_device → smc_listen_prfx_check → smc_clc_prfx_match), and the peer controls the fields that select and drive the code path. Any host running an AF_SMC listener is exposed to unauthenticated remote connections.\nAC:H - The attacker fully controls one side of the race (when the CLC Proposal arrives and thus when the stale dst->dev is dereferenced), but the other side requires the route's net_device to be concurrently torn down via dst_dev_put()/free_netdev(), which a remote attacker cannot induce or time.\nPR:N - The CLC handshake is the first exchange on the connection and SMC performs no authentication before smc_clc_prfx_match() runs, so an unauthenticated remote attacker reaches the bug with no credentials of any kind.\nUI:N - Triggering requires only that the attacker complete a TCP handshake with the SMC option and send a CLC Proposal; no action by any local user or administrator is needed.\nS:U - The use-after-free is confined to kernel memory (the net_device slab and the in_dev/inet6_dev structures it points at) within the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The freed net_device is dereferenced and its ifa_list/addr_list walked, and since a reclaimed slab can be groomed with attacker-controlled data this yields an arbitrary kernel-memory read primitive; the match/no-match outcome is additionally returned to the peer as SMC_CLC_DECL_DIFFPREFIX, forming a remotely observable oracle on freed memory contents.\nI:H - A use-after-free of a net_device is a heap-corruption primitive: the reclaimed object's contents are attacker-influencable via heap spraying and the code follows pointers out of it, which can be groomed into an arbitrary write and control-flow hijack.\nA:H - Dereferencing the freed net_device and walking a bogus in_dev/inet6_dev address list reliably produces a kernel oops, panic, or an unbounded list walk, crashing the system." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/smc/smc_clc.c" ], "versions": [ { "version": "a046d57da19f812216f393e7c535f5858f793ac3", "lessThan": "3f119c37aa293af41400cccb3d89fab8dcf774b0", "status": "affected", "versionType": "git" }, { "version": "a046d57da19f812216f393e7c535f5858f793ac3", "lessThan": "4f5f52a5842937f945582a93cb9daed9ea526fee", "status": "affected", "versionType": "git" }, { "version": "a046d57da19f812216f393e7c535f5858f793ac3", "lessThan": "326e5cf301d0bec0a672aa834d8254c4f9df6255", "status": "affected", "versionType": "git" }, { "version": "a046d57da19f812216f393e7c535f5858f793ac3", "lessThan": "d26e80f7fb62d77757b67a1b94e4ac756bc9c658", "status": "affected", "versionType": "git" }, { "version": "a046d57da19f812216f393e7c535f5858f793ac3", "lessThan": "235f81045c008169cc4e1955b4a64e118eebe61b", "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/smc/smc_clc.c" ], "versions": [ { "version": "4.11", "status": "affected" }, { "version": "0", "lessThan": "4.11", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.187", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.156", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.108", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.17.3", "lessThanOrEqual": "6.17.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18", "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": "4.11", "versionEndExcluding": "6.1.187" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.6.156" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.12.108" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.17.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.18" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/3f119c37aa293af41400cccb3d89fab8dcf774b0" }, { "url": "https://git.kernel.org/stable/c/4f5f52a5842937f945582a93cb9daed9ea526fee" }, { "url": "https://git.kernel.org/stable/c/326e5cf301d0bec0a672aa834d8254c4f9df6255" }, { "url": "https://git.kernel.org/stable/c/d26e80f7fb62d77757b67a1b94e4ac756bc9c658" }, { "url": "https://git.kernel.org/stable/c/235f81045c008169cc4e1955b4a64e118eebe61b" } ], "title": "smc: Use __sk_dst_get() and dst_dev_rcu() in smc_clc_prfx_match().", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-06-16T19:59:59.004592Z", "id": "CVE-2025-40168", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-06-16T20:00:14.873Z" } } ] } }