What is CVE-2016-6337?

CVE-2016-6337 is a high-severity vulnerability in MediaWiki, classified under Improper Access Control. CVSS score: 7.5/10. Published 2017-04-20.

How severe is CVE-2016-6337?

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

Vulnerability in MediaWiki

CVE-2016-6337

MediaWiki 1.27.x before 1.27.1 might allow remote attackers to bypass intended session access restrictions by leveraging a call to the UserGetRights function after Session::getAllowedUserRights.

Published 2017-04-20 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.012 (67.8th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 68th percentile — 67.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.012 · newest: 0.012 · change: 0.000

Affected products

MediaWiki — versions 1.27.0

Weakness classification (CWE)

CWE-284 — Improper Access Control

References

phabricator.wikimedia.org/T139670 (Patch, Third Party Advisory)
lists.wikimedia.org/pipermail/mediawiki-announce/2016-August/000195.html (Vendor Advisory, mailing-list, Patch, Mailing List)

Frequently asked questions

What is CVE-2016-6337?: CVE-2016-6337 is a high-severity vulnerability in MediaWiki, classified under Improper Access Control. CVSS score: 7.5/10. Published 2017-04-20.
How severe is CVE-2016-6337?: High severity. CVSS v3 base score is 7.5 out of 10.