USN-8688-2: PAM vulnerability
Publication date
1 September 2026
Overview
A system hardening measure could be bypassed.
Releases
Packages
- pam - Pluggable Authentication Modules
Details
USN-8688-1 fixed a vulnerability in PAM. This update provides the
corresponding fix for PAM on Ubuntu 26.04 LTS.
Original advisory details:
Juthawong Naisanguansee discovered that PAM incorrectly cleared failed
login attempt records when certain services invoked the account phase
without first performing authentication. An attacker could possibly use
this issue to reset failed login counters, resulting in authentication
lockout restrictions being bypassed.
USN-8688-1 fixed a vulnerability in PAM. This update provides the
corresponding fix for PAM on Ubuntu 26.04 LTS.
Original advisory details:
Juthawong Naisanguansee discovered that PAM incorrectly cleared failed
login attempt records when certain services invoked the account phase
without first performing authentication. An attacker could possibly use
this issue to reset failed login counters, resulting in authentication
lockout restrictions being bypassed.
Update instructions
After a standard system update you need to reboot your computer to make all the necessary changes.
Learn more about how to get the fixes.The problem can be corrected by updating your system to the following package versions:
| Ubuntu Release | Package Version | ||
|---|---|---|---|
| 26.04 LTS resolute | libpam-modules – 1.7.0-5ubuntu3.2 | ||
| libpam-modules-bin – 1.7.0-5ubuntu3.2 | |||
| libpam-runtime – 1.7.0-5ubuntu3.2 | |||
| libpam0g – 1.7.0-5ubuntu3.2 | |||
| libpam0g-dev – 1.7.0-5ubuntu3.2 | |||
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