Vulnerability · Published Feb 10, 2025 · Assigned by GitHub_M
CVE-2025-24032PAM-PKCS#11 vulnerable to authentication bypass with default value for `cert_policy` (`none`)
Critical 9.2
In plain English
A critical-severity improper authentication in pam_pkcs11 from OpenSC. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 54% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
PAM-PKCS#11 is a Linux-PAM login module that allows a X.509 certificate based user login. Prior to version 0.6.13, if cert_policy is set to none (the default value), then pam_pkcs11 will only check if the user is capable of logging into the token. An attacker may create a different token with the user's public data (e.g. the user's certificate) and a PIN known to the attacker. If no signature with the private key is required, then the attacker may now login as user with that created token. The default to *not* check the private key's signature has been changed with commit commi6638576892b59a99389043c90a1e7dd4d783b921, so that all versions starting with pam_pkcs11-0.6.0 should be affected. As a workaround, in `pam_pkcs11.conf`, set at least `cert_policy = signature;`.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | pam-pkcs11 | 0.6.12-1+deb12u1 | DSA-5864-1 |
| Debian:12 | pam-pkcs11 | 0.6.12-1+deb12u1 | DEBIAN-CVE-2025-24032 |
| Debian:13 | pam-pkcs11 | 0.6.13-1 | DEBIAN-CVE-2025-24032 |
| Debian:14 | pam-pkcs11 | 0.6.13-1 | DEBIAN-CVE-2025-24032 |
| Ubuntu:22.04:LTS | pam-pkcs11 | 0.6.11-4ubuntu0.1 | USN-7363-1 |
| Ubuntu:22.04:LTS | pam-pkcs11 | 0.6.11-4ubuntu0.1 | UBUNTU-CVE-2025-24032 |
| Ubuntu:24.04:LTS | pam-pkcs11 | 0.6.12-2ubuntu0.24.04.1 | UBUNTU-CVE-2025-24032 |
| Ubuntu:24.04:LTS | pam-pkcs11 | 0.6.12-2ubuntu0.24.04.1 | USN-7363-1 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| OpenSC | pam_pkcs11 | < 0.6.13 |
Weakness: CWE-287 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:L/SI:L/SA:L
References
- https://github.com/OpenSC/pam_pkcs11/security/advisories/GHSA-8r8p-7mgp-vf56 x_refsource_CONFIRM
- https://github.com/OpenSC/pam_pkcs11/commit/470263258d1ac59c5eade439c4d9caba0097e6e6 x_refsource_MISC
- https://github.com/OpenSC/pam_pkcs11/commit/b665b287ff955bbbd9539252ff9f9e2754c3fb48 x_refsource_MISC
- https://github.com/OpenSC/pam_pkcs11/commit/d9530167966a77115db6e885d459382a2e52ee9e x_refsource_MISC
- https://github.com/OpenSC/pam_pkcs11/releases/tag/pam_pkcs11-0.6.13 x_refsource_MISC
- https://lists.debian.org/debian-lts-announce/2025/02/msg00021.html
- https://www.vicarius.io/vsociety/posts/cve-2025-24032-detect-vulnerability-in-linux-pam-module
- https://www.vicarius.io/vsociety/posts/cve-2025-24032-mitigate-linux-pam-module-vulnerability