Auth bypass in Linux-Pam

CVE-2020-27780

A flaw was found in Linux-Pam in versions prior to 1.5.1 in the way it handle empty passwords for non-existing users. When the user doesn't exist PAM try to authenticate with root and in the case of an empty password it successfully authenticate.

Vulnerability class: Broken Authentication

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.020 (79.8th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 80th percentile — 79.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2020-27780: held from 0.020 to 0.020.

EPSS over last 30 days · oldest: 0.020 · newest: 0.020 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-27780?
CVE-2020-27780 is a critical-severity vulnerability in Linux-Pam, classified under Improper Authentication. CVSS score: 9.8/10. Published 2020-12-18.
How severe is CVE-2020-27780?
Critical severity. CVSS v3 base score is 9.8 out of 10.