{"cve":"CVE-2026-98173","nvd":{"published":"2026-10-06T09:17:59.060","modified":"2026-10-21T13:21:25.150","status":"Received","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H","score":7.5},"cwes":[],"references":["https://git.kernel.org/stable/c/c941f1ebfd26f683de81091473f3596a218abff0","https://git.kernel.org/stable/c/d034e836eefd7ce75e588f7031cffbeec594f5ac","https://git.kernel.org/stable/c/e99040e5e9c60441e6b4725e1a7b88c3106ae903","https://git.kernel.org/stable/c/ec36b38e65596950e6c29bed7dfc90b98707c19c","https://git.kernel.org/stable/c/ee0d8f83d68f6e6509f092c997ccab3c8c801538"],"products":[],"source":"nvd","synced_at":"2026-10-22T16:41:11.231219466+00:00"},"epss":{"cve":"CVE-2026-98173","score":0.00321,"percentile":0.24856,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}