Auth bypass in MediaWiki

CVE-2021-35197

In MediaWiki before 1.31.15, 1.32.x through 1.35.x before 1.35.3, and 1.36.x before 1.36.1, bots have certain unintended API access. When a bot account has a "sitewide block" applied, it is able to still "purge" pages through the MediaWiki Action API (which a "sitewide block" should have prevented).

Vulnerability class: Broken Access Control

EPSS: 0.019 (78.1th percentile) — read the EPSS interpretation.

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:N/I:H/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-35197?
CVE-2021-35197 is a high-severity vulnerability in MediaWiki, classified under Incorrect Authorization. CVSS score: 7.5/10. Published 2021-07-02.
How severe is CVE-2021-35197?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2021-35197 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.