What’s Vulnerable › Vulnerabilities
CVE-2021-35197
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 1.9% probability of exploitation in the next 30 days
- Public exploit or detection template: yes
- Published: 2021-07-02 · updated 2026-06-17
- Weakness: CWE-863
Description
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).
Affected products
- Debian Linux: 9.0, 10.0, 11.0
- Fedoraproject Fedora: 33, 34, 35
- Wikimedia Foundation MediaWiki: before 1.31.15; from 1.32.0 before 1.35.3; from 1.36.0 before 1.36.1 — fixed in 1.31.15, 1.35.3, 1.36.1
How to fix
Upgrade to a fixed version: Wikimedia Foundation MediaWiki 1.31.15, 1.35.3, 1.36.1. Check the vendor advisory for mitigations.
References
- https://lists.debian.org/debian-lts-announce/2021/10/msg00003.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CJDYJQWT43GBD6GNQ4OW7JOZ6WQ6DZTN/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MDBPECBWN6LWNSWIQMVXK6PP4YFEUYHA/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QNEAI2T3Y65I55ZB6UE6RMC662RZTGRX/
- https://lists.wikimedia.org/hyperkitty/list/mediawiki-announce%40lists.wikimedia.org/thread/YR3X4L2CPSEJVSY543AWEO65TD6APXHP/
- https://phabricator.wikimedia.org/T280226
- https://security.gentoo.org/glsa/202107-40
- https://www.debian.org/security/2021/dsa-4979
- https://lists.debian.org/debian-lts-announce/2021/10/msg00003.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CJDYJQWT43GBD6GNQ4OW7JOZ6WQ6DZTN/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MDBPECBWN6LWNSWIQMVXK6PP4YFEUYHA/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QNEAI2T3Y65I55ZB6UE6RMC662RZTGRX/
Get alerted when CVE-2021-35197 or the next vulnerability affects your stack