CVE-2026-48981: mcdope pam_usb · XML External Entity (XXE)
Affects mcdope pam_usbSource CVE Database V5
Not known to be exploited · CVSS 6.7 Medium : upgrade to 0.9.2 when convenient.
Data as of 31 Oct 2026, 08:20 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 4% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.9.2
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:LExploitation evidence
Disclosed: evidence found.
CVE published 18 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade pam_usb and mcdope/pam_usb to 0.9.2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| mcdopepam_usb | Affected
| Fixed in
|
GitHubmcdope/pam_usbpkg:github/mcdope/pam_usbOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade pam_usb to version 0.9.2 or later where this vulnerability is fixed. Since the vulnerability requires a crafted configuration file, ensure strict access controls on pam_usb.conf to prevent unauthorized modifications. Patch status is confirmed fixed in version 0.9.2.
Description
pam_usb provides hardware authentication for Linux using ordinary removable media. In versions prior to 0.9.2, pam_usb calls xmlReadFile() with flags=0 when loading the configuration file, allowing libxml2 to process external entity references (XXE), potentially making outbound network connections or local file reads at XML parse time from the context of the authenticating process. The vulnerability requires the configuration file to contain crafted XML entity references. Since pam_usb.conf is root-owned, direct exploitation requires prior write access to the config, but the defence-in-depth impact is significant given that pam_usb.so runs in setuid contexts (sudo, su). This issue has been fixed in version 0.9.2.