CVE-2026-44709 — pam_usb: PINENTRY_FALLBACK_APP environment variable allows arbitrary command execution
pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.8.7, pamusb-pinentry reads the PINENTRY_FALLBACK_APP environment variable and execu…
Published: 2026-05-27 · CVSS: 7.8 · CVSS 3.1
pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.8.7, pamusb-pinentry reads the PINENTRY_FALLBACK_APP environment variable and executes it directly without any validation. Any process that can set environment variables before pamusb-pinentry is invoked can point PINENTRY_FALLBACK_APP at an arbitrary binary or script and have it executed with the privileges of the pam_usb tool chain. This vulnerability is fixed in 0.8.7.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7