CVE-2026-44709 (GCVE-0-2026-44709)

Vulnerability from cvelistv5 – Published: 2026-05-27 20:20 – Updated: 2026-06-02 17:59
VLAI
Title
pam_usb: PINENTRY_FALLBACK_APP environment variable allows arbitrary command execution
Summary
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.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
  • CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Assigner
References
Impacted products
Vendor Product Version
mcdope pam_usb Affected: < 0.8.7
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.