CVE-2021-31552 json
An issue was discovered in the AbuseFilter extension for MediaWiki through 1.35.2.
published 2021-04-22 5 y ago modified 2026-06-17 4 mo ago also BIT-mediawiki-2021-31552 , EUVD-2021-18449
- cvss
- 5.4
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 47%
- public exploits
- 0
- none known
Summary
An issue was discovered in the AbuseFilter extension for MediaWiki through 1.35.2. It incorrectly executed certain rules related to blocking accounts after account creation. Such rules would allow for user accounts to be created while blocking only the IP address used to create an account (and not the user account itself). Such rules could also be used by a nefarious, unprivileged user to catalog and enumerate any number of IP addresses related to these account creations.
Patch / fix
- bitnami mediawiki 1.35.3
Exploit prediction
0.58% chance of exploitation in the next 30 days, higher than 47% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N |
| NVD | 2.0 | 5.5 | AV:N/AC:L/Au:S/C:P/I:P/A:N |
| OSV | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| bitnami | mediawiki | <1.35.3 |
1.35.3 |
Classification
- Weakness
-
- CWE-863 Incorrect Authorization
References
-
gerrit.wikimedia.org
/r/q/I8bae477ad7e4d0190335363ac2decf28e4313da1
issue-tracking, vendor-advisory, web
-
phabricator.wikimedia.org
/T152394
third-party-advisory, web
-
nvd.nist.gov
/vuln/detail/CVE-2021-31552
web
Sources
- CVE List CVE-2021-31552
- NVD CVE-2021-31552
- OSV BIT-mediawiki-2021-31552
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