CVE-2026-48792 (GCVE-0-2026-48792)

Vulnerability from cvelistv5 – Published: 2026-05-27 19:55 – Updated: 2026-05-28 13:27
VLAI
Title
pam_usb: pusb_has_virtual_input_device() silently discards EACCES, disabling remote desktop detection under non-root execution
Summary
pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.9.1, src/evdev.c silently ignores EACCES errors when opening /dev/input/event* nodes, causing pusb_has_virtual_input_device() to return 0 (no virtual devices found) even when every open() call failed due to insufficient permissions. The caller in src/local.c cannot distinguish a clean absence of virtual devices from a permission-denied scan, and acts on the false negative by continuing authentication without denying. This vulnerability is fixed in 0.9.1.
Severity
4.4 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
CWE
  • CWE-390 - Detection of Error Condition Without Action
  • CWE-693 - Protection Mechanism Failure
Assigner
References
Impacted products
Vendor Product Version
mcdope pam_usb Affected: < 0.9.1
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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.

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  • 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.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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