pam_usb: PINENTRY_FALLBACK_APP environment variable allows arbitrary command execution_CVE-2026-44709

7.8 / 10

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Description

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.

Basic Information

ID CVE-2026-44709

Source GitHub_M

Published May 27, 2026 at 20:20

Affected Product

Vendor mcdope

Product pam_usb

Version < 0.8.7

Affected Versions mcdope pam_usb < 0.8.7

CWE Classification

CWE-78

References

github.com /mcdope/pam_usb/security/advisories/GHSA-jxrj-q67x-wr4c

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    "published": "2026-05-27T20:20:52.529Z",
    "modified": "2026-05-27T20:20:52.529Z",
    "type": "cve",
    "title": "pam_usb: PINENTRY_FALLBACK_APP environment variable allows arbitrary command execution",
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