6.3
MEDIUM CVSS 3.1
CVE-2026-47274
pam_usb: Uncontrolled search path in pam_usb tools allows privilege escalation via PATH manipulation
Description

pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.9.0, multiple pam_usb helper tools resolved external binaries through the PATH environment variable rather than using absolute paths. An attacker who can influence the process environment during PAM authentication or tool execution could substitute malicious binaries. The affected tools are pamusb-check (src/tmux.c), pamusb-conf (tools/pamusb-conf), and pamusb-keyring-unlock-gnome (tools/pamusb-keyring-unlock-gnome). This vulnerability is fixed in 0.9.0.

INFO

Published Date :

May 27, 2026, 8:16 p.m.

Last Modified :

May 27, 2026, 8:16 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-47274 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update pam_usb to version 0.9.0 or later to fix authentication vulnerabilities.
  • Update pam_usb to version 0.9.0.
  • Ensure helper tools use absolute paths.
  • Review process environment during PAM authentication.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-47274 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-47274 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-47274 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-47274 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    May. 27, 2026

    Action Type Old Value New Value
    Added Description pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.9.0, multiple pam_usb helper tools resolved external binaries through the PATH environment variable rather than using absolute paths. An attacker who can influence the process environment during PAM authentication or tool execution could substitute malicious binaries. The affected tools are pamusb-check (src/tmux.c), pamusb-conf (tools/pamusb-conf), and pamusb-keyring-unlock-gnome (tools/pamusb-keyring-unlock-gnome). This vulnerability is fixed in 0.9.0.
    Added CVSS V3.1 AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
    Added CWE CWE-427
    Added Reference https://github.com/mcdope/pam_usb/commit/1ee8745920388df48d001a8e61ba629071557937
    Added Reference https://github.com/mcdope/pam_usb/commit/52a1fd6413b7ffcc1a5b58ce432be42e7bf0dbd0
    Added Reference https://github.com/mcdope/pam_usb/commit/993e73d8bebb1d8e62677388de3402b6ec36b600
    Added Reference https://github.com/mcdope/pam_usb/security/advisories/GHSA-pp29-w28g-r9h9
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.