What is CVE-2011-4973?

CVE-2011-4973 is a critical-severity vulnerability in Mod Nss Project, classified under Improper Authentication. CVSS score: 9.8/10. Published 2018-02-15.

How severe is CVE-2011-4973?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Auth bypass in Mod Nss Project

CVE-2011-4973

Authentication bypass vulnerability in mod_nss 1.0.8 allows remote attackers to assume the identity of a valid user by using their certificate and entering 'password' as the password.

Vulnerability class: Broken Authentication

Published 2018-02-15 · last modified 2026-06-16.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.010 (61.3th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 61st percentile — 61.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000

Affected products

Mod Nss Project — versions 1.0.8

Weakness classification (CWE)

CWE-287 — Improper Authentication

References

bugzilla.redhat.com/show_bug.cgi (Third Party Advisory, Issue Tracking)
www.redhat.com/archives/mod_nss-list/2011-May/msg00001.html (mailing-list, Third Party Advisory, Issue Tracking)

Frequently asked questions

What is CVE-2011-4973?: CVE-2011-4973 is a critical-severity vulnerability in Mod Nss Project, classified under Improper Authentication. CVSS score: 9.8/10. Published 2018-02-15.
How severe is CVE-2011-4973?: Critical severity. CVSS v3 base score is 9.8 out of 10.