CVE-2020-27957 json
The RandomGameUnit extension for MediaWiki through 1.35 was not properly escaping various title-related data.
published 2020-10-28 6 y ago modified 2026-06-17 4 mo ago also BIT-mediawiki-2020-27957 , EUVD-2020-20449
- cvss
- 5.4
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 53%
- public exploits
- 0
- none known
Summary
The RandomGameUnit extension for MediaWiki through 1.35 was not properly escaping various title-related data. When certain varieties of games were created within MediaWiki, their names or titles could be manipulated to generate stored XSS within the RandomGameUnit extension.
Patch / fix
- bitnami mediawiki 1.35.1
Exploit prediction
0.69% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- phabricator.wikimedia.org https://phabricator.wikimedia.org/T266400 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 3.5 | AV:N/AC:M/Au:S/C:N/I:P/A:N |
| OSV | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| bitnami | mediawiki | <1.35.1 |
1.35.1 |
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
gerrit.wikimedia.org
/r/q/I497d2076038f75c9eb77e0e250f2af56f5bd2bfc
patch, vendor-advisory, web
-
phabricator.wikimedia.org
/T266400
exploit, vendor-advisory, web
-
nvd.nist.gov
/vuln/detail/CVE-2020-27957
web
Sources
- CVE List CVE-2020-27957
- NVD CVE-2020-27957
- OSV BIT-mediawiki-2020-27957
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