6.5

CVE-2026-47273: pam_usb: XPath injection via PAM-supplied identifiers in pam_usb configuration queries

Deferred
Published 27-05-2026Last modified 28-05-2026

Vulnerability summary

CVE-2026-47273 is a medium (CVSS 6.5) vulnerability in mcdope pam_usb. EPSS estimates a 0.41% chance of exploitation in the next 30 days, higher than 34% of scored vulnerabilities.

Overall risk
26/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.41%
0%100%
Low · +0.14 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 27-05-2026
    PublishedVulnerability first disclosed.
  2. 28-05-2026
    Last modifiedVulnerability information updated.

Description

pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.9.0, pam_usb builds XPath expressions from user-supplied identifiers (PAM username, service name) and device-supplied identifiers (USB device serial, model, vendor) to query /etc/pamusb.conf. These identifiers were not validated for XPath metacharacters, allowing injection of arbitrary XPath predicates. This vulnerability is fixed in 0.9.0.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.41%

Chance of exploitation in the next 30 days

Percentile

34%

Versus all other CVEs

30-day change

Increase +0.14 pp

From 0.27% on 22-09-2026

22-09-202622-10-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Mcdope1 product

1 vendor · 1 product

References

3 links