{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-80980", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-26T14:34:25.811Z", "datePublished": "2026-09-11T19:42:40.832Z", "dateUpdated": "2026-10-21T12:47:21.045Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:47:21.045Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: stop killed, freed and out_of_sync sharing a byte\n\nThe three connection state flags are single-bit bitfields, so they occupy\none byte of struct smc_connection and every store to one is a\nread-modify-write of the other two:\n\n u8 killed : 1;\n u8 freed : 1;\n u8 out_of_sync : 1;\n\nThey are not written under a common lock. smc_cdc_msg_validate() sets\nout_of_sync from the receive tasklet, while smc_conn_kill() sets killed\nfrom process context under lock_sock(), and the receive path does not defer\nto the backlog when the socket is owned -- smc_cdc_msg_recv() takes only\nbh_lock_sock().\n\nGive each flag its own byte so a store no longer touches its neighbours.\nAll readers test them as booleans and are unchanged. struct smc_connection\ngrows by two bytes." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - smc_cdc_msg_validate() runs from the SMC-R CDC receive tasklet on RDMA completions, and teardown is driven by CLC DECLINE (FIRST_CONTACT) or LLC DELETE_LINK_ALL from the same peer. SMC-Rv2 is RoCEv2 over UDP/4791 (IP-routable) with the CLC handshake on plain TCP, so a remote host that can reach an AF_SMC listener hits the path.\nAC:L - The attacker controls both sides of the race: it sends CDC failover_validation messages that store out_of_sync from the receive tasklet (no sock lock) while concurrently forcing smc_conn_kill()/smc_conn_free() via CLC decline, CDC close/abort, or LLC link-delete, and can retry across many connections in the same link group.\nPR:N - SMC has no peer authentication. Completing the CLC handshake to a listening AF_SMC/IPPROTO_SMC socket and sending CDC/CLC/LLC messages requires no credentials, capabilities, or local account, matching other SMC remote bugs.\nUI:N - CDC is processed in a softirq tasklet from the RDMA completion queue and CLC decline is handled in the handshake worker; no local user or application action is required beyond the already-listening SMC server.\nS:U - The corrupted flags and resulting UAF stay inside kernel objects (smc_connection, smc_sock, smc_link_group) in the same security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - A lost killed/freed/out_of_sync bit from the shared-byte RMW lets CDC continue after unregister or lets smc_conn_free() run twice (duplicate smc_lgr_put), a use-after-free of the socket and link group that can be reallocated to disclose kernel memory.\nI:H - The same UAF/double-free writes through a reused smc_sock (sk_err, sk_data_ready, queue_work on abort_work/close_work) and link-group refcounts, giving heap-spray primitives for arbitrary kernel write and control-flow hijack.\nA:H - Use-after-free and double-free of the connection and link group oops or panic in softirq/workqueue context (refcount underflow, as in related SMC UAFs), and the attacker can trigger it repeatedly without authentication." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/smc/smc.h" ], "versions": [ { "version": "b286a0651e4404ab96cdfdcdad8a839a26b3751e", "lessThan": "297e96f38d3e4f1a3b84068950dd5c7a55bbdc7b", "status": "affected", "versionType": "git" }, { "version": "b286a0651e4404ab96cdfdcdad8a839a26b3751e", "lessThan": "09a9cbadc05f452405de31012bd2c428b601291a", "status": "affected", "versionType": "git" }, { "version": "b286a0651e4404ab96cdfdcdad8a839a26b3751e", "lessThan": "313f79149eb337411c64e2c247234b62ef9a3cb9", "status": "affected", "versionType": "git" }, { "version": "b286a0651e4404ab96cdfdcdad8a839a26b3751e", "lessThan": "2cb7a8d64b7e8ccdc69bbe48fe9c4eaa79c33aec", "status": "affected", "versionType": "git" }, { "version": "b286a0651e4404ab96cdfdcdad8a839a26b3751e", "lessThan": "db51a8658c11a82432b64999519a269c3aabb447", "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.h" ], "versions": [ { "version": "5.8", "status": "affected" }, { "version": "0", "lessThan": "5.8", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.112", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.50", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "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": "5.8", "versionEndExcluding": "6.6.160" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.8", "versionEndExcluding": "6.12.112" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.8", "versionEndExcluding": "6.18.50" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.8", "versionEndExcluding": "7.2.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.8", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/297e96f38d3e4f1a3b84068950dd5c7a55bbdc7b" }, { "url": "https://git.kernel.org/stable/c/09a9cbadc05f452405de31012bd2c428b601291a" }, { "url": "https://git.kernel.org/stable/c/313f79149eb337411c64e2c247234b62ef9a3cb9" }, { "url": "https://git.kernel.org/stable/c/2cb7a8d64b7e8ccdc69bbe48fe9c4eaa79c33aec" }, { "url": "https://git.kernel.org/stable/c/db51a8658c11a82432b64999519a269c3aabb447" } ], "title": "net/smc: stop killed, freed and out_of_sync sharing a byte", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-80980", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "yes" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-10-16T19:21:47.866329Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:26:37.381Z" } } ] } }