CVE-2026-54411: medium-severity vulnerability in Linux-PAM
Linux-PAM pam_userdb Observable Timing Discrepancy in Plaintext Password Comparison
Published · Updated
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.9epss 0.5%
exploitation probability
0.5%top 59% of all CVEs
observed exploitation
nono source reports it
Linux-PAM through 1.7.2 contains an observable timing discrepancy (CWE-208) in the pam_userdb module's plaintext-password comparison path in modules/pam_userdb/pam_userdb.c that allows a local or network-adjacent attacker able to repeatedly drive authentication through a calling service to recover the plaintext password of a target account by measuring response-timing differences.
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/AU:N/V:D
Affected products
Linux-PAM · Linux-PAM