CVE-2026-48981
June 18, 2026, 8:16 p.m.
6.7
Medium
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.
Product(s) Impacted
| Vendor | Product | Versions |
|---|---|---|
| Pam Usb |
|
|
| Xmlsoft |
|
|
Weaknesses
Common security weaknesses mapped to this vulnerability.
CWE-611
Improper Restriction of XML External Entity Reference
The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.
*CPE(s)
Affected systems and software identified for this CVE.
| Type | Vendor | Product | Version | Update | Edition | Language | Software Edition | Target Software | Target Hardware | Other Information |
|---|---|---|---|---|---|---|---|---|---|---|
| a | pam_usb | pam_usb | <0.9.2 | / | / | / | / | / | / | / |
| a | xmlsoft | libxml2 | / | / | / | / | / | / | / | / |
Tags
CVSS Score
CVSS Data - 3.1
- Attack Vector: LOCAL
- Attack Complexity: HIGH
- Privileges Required: HIGH
- Scope: CHANGED
- Confidentiality Impact: HIGH
- Integrity Impact: LOW
- Availability Impact: LOW
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:L
Timeline
Published: June 18, 2026, 8:16 p.m.
Last Modified: June 18, 2026, 8:16 p.m.
Last Modified: June 18, 2026, 8:16 p.m.
Status : Received
CVE has been recently published to the CVE List and has been received by the NVD.
More infoSource
*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.