{"schema":"threatline.record/2","record":{"id":"CVE-2026-98173","aliases":[],"summary":"smb: client: fix use-after-free of iface in cifs_try_adding_channels()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix use-after-free of iface in cifs_try_adding_channels()\n\ncifs_try_adding_channels() iterates ses->iface_list with\nlist_for_each_entry_safe_from(), which captures the next entry\n(niface) under iface_lock.  The loop body then drops iface_lock for\nthe whole duration of cifs_ses_add_channel().\n\nA concurrent interface refresh (SMB3_request_interfaces() ->\nparse_server_interfaces()) marks all ifaces inactive and removes and\nfrees any that are not re-advertised via list_del() + kref_put(),\nwhere release_iface() is a bare kfree().  Since niface typically has\nno channel holding a reference, the list reference is its last and it\ncan be freed inside the unlocked window.  On continue, the iterator\nadvance step then dereferences niface->iface_head.next, and the loop\nbody reads iface->rdma_capable/is_active, both on freed memory.\n\nFix this by never keeping an unreferenced list pointer across the\nunlocked window.  Each channel attempt now re-scans the list from the\nhead under iface_lock, takes a kref on the selected candidate, and\npasses only that referenced candidate to cifs_ses_add_channel().\nweight_fulfilled still tracks selection progress, so restarting the\nscan preserves the original weighted distribution and the\nweight_fulfilled-before-kref_put ordering on the failure path.\n\nAdd a per-pass attempts cap so a flapping interface refresh cannot\nkeep the inner loop spinning within a single tries increment.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98173","source_modified_at":"2026-10-21T12:54:49.437Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"aa45dadd34e44fcd6a9df4b395bee5b5633b4cec","lessThan":"ee0d8f83d68f6e6509f092c997ccab3c8c801538","status":"affected","versionType":"git"},{"version":"aa45dadd34e44fcd6a9df4b395bee5b5633b4cec","lessThan":"c941f1ebfd26f683de81091473f3596a218abff0","status":"affected","versionType":"git"},{"version":"aa45dadd34e44fcd6a9df4b395bee5b5633b4cec","lessThan":"e99040e5e9c60441e6b4725e1a7b88c3106ae903","status":"affected","versionType":"git"},{"version":"aa45dadd34e44fcd6a9df4b395bee5b5633b4cec","lessThan":"ec36b38e65596950e6c29bed7dfc90b98707c19c","status":"affected","versionType":"git"},{"version":"aa45dadd34e44fcd6a9df4b395bee5b5633b4cec","lessThan":"d034e836eefd7ce75e588f7031cffbeec594f5ac","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98173","source_modified_at":"2026-10-21T12:54:49.437Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"5.19","status":"affected"},{"version":"0","lessThan":"5.19","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":"6.18.54","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.8","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}],"defaultStatus":"affected"}],"fixed_versions":[],"cvss":7.5,"severity":"High","kev":{"listed":false},"epss":{"probability":0.00325,"percentile":0.24383,"score_date":"2026-10-23"},"published_at":"2026-10-06T08:44:17.567Z","modified_at":"2026-10-21T12:54:49.437Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-98173","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-21T12:54:49.437Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-98173","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/ee0d8f83d68f6e6509f092c997ccab3c8c801538"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/c941f1ebfd26f683de81091473f3596a218abff0"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/e99040e5e9c60441e6b4725e1a7b88c3106ae903"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/ec36b38e65596950e6c29bed7dfc90b98707c19c"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/d034e836eefd7ce75e588f7031cffbeec594f5ac"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-21T12:54:49.437Z","content_hash":"cf7638518fedbd72c46f793c4e3b61e70b3d0379ac4f4bcb58b1e0c015f281ad"}}