{"affected":[{"product":"pam_usb","source":"CNA: GitHub_M","vendor":"mcdope","versions":[{"status":"affected","version":">= 0.8.0, < 0.9.3"}]}],"cveId":"CVE-2026-64668","cwes":["CWE-285","CWE-693"],"description":"pam_usb provides hardware authentication for Linux using removable media. From version 0.8.0 to before version 0.9.3, the deny_remote feature in pam_usb uses /usr/bin/w -i to detect whether the authenticating user has an active remote tmux session. In pusb_tmux_has_remote_clients() (src/tmux.c), the IPv6 detection pattern matched the address group and then immediately expected whitespace. On Linux systems with multi-homed network interfaces, w -i appends a zone index (scope identifier) to link-local IPv6 addresses — e.g. fe80::1%eth0. The %eth0 suffix appeared between the address and the next whitespace field, causing the regex match to fail even for an otherwise-matching remote session. The function returned \"no remote clients\" and granted access. This issue has been patched in version 0.9.3.","epss":null,"exploits":[],"kev":null,"metrics":[{"score":7.4,"severity":"high","source":"CNA: GitHub_M","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","version":"3.1"}],"modifiedAt":1794369014037,"publishedAt":1794369014037,"references":[{"source":"CNA: GitHub_M","tags":["x_refsource_CONFIRM"],"url":"https://github.com/mcdope/pam_usb/security/advisories/GHSA-7583-9cqv-j9rf"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/mcdope/pam_usb/pull/423"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/mcdope/pam_usb/commit/a62513f3da871d6576d751de3482eb80b9ac79f3"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/mcdope/pam_usb/releases/tag/0.9.3"}],"remediation":[],"revision":"649a37202495157d9855eecf188b5b5b119e03b272732344aa2df75e4a4eda05","sources":[{"modifiedAt":1794369014037,"name":"CNA: GitHub_M","retrievedAt":1794370177687,"url":"https://www.cve.org/CVERecord?id=CVE-2026-64668"}],"ssvc":null,"status":"published","title":"pam_usb: deny_remote bypassed by zone-indexed IPv6 addresses (fe80::1%eth0) in pusb_tmux_has_remote_clients","updatedAt":1794370177687}