OpenSC pam_pkcs11 up to 0.6.12 X.509 Certificate null pointer dereference

Summaryinfo

A vulnerability was found in OpenSC pam_pkcs11 up to 0.6.12. It has been rated as problematic. Impacted is an unknown function of the component X.509 Certificate Handler. Performing a manipulation results in null pointer dereference. This vulnerability was named CVE-2025-24031. The attack needs to be approached locally. There is no available exploit.

Detailsinfo

A vulnerability, which was classified as problematic, was found in OpenSC pam_pkcs11 up to 0.6.12. This affects an unknown function of the component X.509 Certificate Handler. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. The summary by CVE is:

PAM-PKCS#11 is a Linux-PAM login module that allows a X.509 certificate based user login. In versions 0.6.12 and prior, the pam_pkcs11 module segfaults when a user presses ctrl-c/ctrl-d when they are asked for a PIN. When a user enters no PIN at all, `pam_get_pwd` will never initialize the password buffer pointer and as such `cleanse` will try to dereference an uninitialized pointer. On my system this pointer happens to have the value 3 most of the time when running sudo and as such it will segfault. The most likely impact to a system affected by this issue is an availability impact due to a daemon that uses PAM crashing. As of time of publication, a patch for the issue is unavailable.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2025-24031 since 01/16/2025. The exploitability is told to be easy. An attack has to be approached locally. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 216733 (SUSE SLED15 / SLES15 / openSUSE 15 Security Update : pam_pkcs11 (SUSE-SU-2025:0689-1)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (216733). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• OpenSC

Name

• pam_pkcs11

Version

• 0.6.0
• 0.6.1
• 0.6.2
• 0.6.3
• 0.6.4
• 0.6.5
• 0.6.6
• 0.6.7
• 0.6.8
• 0.6.9
• 0.6.10
• 0.6.11
• 0.6.12

License

• open-source

Website

• Product: https://github.com/OpenSC/pam_pkcs11/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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