What is CVE-2020-25869?

CVE-2020-25869 is a high-severity vulnerability in MediaWiki, classified under Incorrect Authorization. CVSS score: 7.5/10. Published 2020-09-27.

How severe is CVE-2020-25869?

High severity. CVSS v3 base score is 7.5 out of 10.

Auth bypass in MediaWiki

CVE-2020-25869

An information leak was discovered in MediaWiki before 1.31.10 and 1.32.x through 1.34.x before 1.34.4. Handling of actor ID does not necessarily use the correct database or correct wiki.

Vulnerability class: Broken Access Control

Published 2020-09-27 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.014 (71.6th percentile), scored 2026-10-01.

Low probability of exploitation in the next 30 days, but still tracked. 72nd percentile — 71.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.014 · newest: 0.014 · change: 0.000

Affected products

MediaWiki
Fedoraproject Fedora — versions 33

Weakness classification (CWE)

CWE-863 — Incorrect Authorization

References

phabricator.wikimedia.org/T260485 (Permissions Required, Vendor Advisory)
lists.wikimedia.org/pipermail/mediawiki-l/2020-September/048480.html (Mailing List, Vendor Advisory)
lists.wikimedia.org/pipermail/mediawiki-l/2020-September/048488.html (Mailing List, Vendor Advisory)
lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)

Frequently asked questions

What is CVE-2020-25869?: CVE-2020-25869 is a high-severity vulnerability in MediaWiki, classified under Incorrect Authorization. CVSS score: 7.5/10. Published 2020-09-27.
How severe is CVE-2020-25869?: High severity. CVSS v3 base score is 7.5 out of 10.