CVE-2026-48792

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.

CVSS v3 4.4 MEDIUM

4.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 2.5

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/mcdope/pam_usb/issues/351
https://github.com/mcdope/pam_usb/issues/55
https://github.com/mcdope/pam_usb/security/advisories/GHSA-pvrg-chgw-x42c

Configurations

No configuration.

History

26 Oct 2026, 11:10

Type	Values Removed	Values Added
Summary		(es) pam_usb proporciona autenticación de hardware para Linux utilizando medios extraíbles comunes. Antes de 0.9.1, src/evdev.c ignora silenciosamente los errores EACCES al abrir los nodos /dev/input/event, lo que provoca que pusb_has_virtual_input_device() devuelva 0 (no se encontraron dispositivos virtuales) incluso cuando cada llamada a open() falló debido a permisos insuficientes. El llamador en src/local.c no puede distinguir una ausencia limpia de dispositivos virtuales de un escaneo con permisos denegados, y actúa sobre el falso negativo al continuar la autenticación sin denegar. Esta vulnerabilidad está corregida en 0.9.1.

Information

Published : 2026-05-27 20:16

Updated : 2026-10-26 11:10

NVD link : CVE-2026-48792

Mitre link : CVE-2026-48792

CVE.ORG link : CVE-2026-48792

JSON object : View

Products Affected

No product.

CWE

CWE-390

Detection of Error Condition Without Action

CWE-693

Protection Mechanism Failure

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