What’s Vulnerable › Vulnerabilities

CVE-2021-39186: Improper Input Validation in GlobalNewFiles

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.0% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-09-01 · updated 2026-06-17
• Weakness: CWE-20

Description

GlobalNewFiles is a MediaWiki extension maintained by Miraheze. Prior to commit number cee254e1b158cdb0ddbea716b1d3edc31fa4fb5d, the username column of the GlobalNewFiles special page is vulnerable to a stored XSS. Commit number cee254e1b158cdb0ddbea716b1d3edc31fa4fb5d contains a patch. As a workaround, one may disallow <,> (or other characters required to insert html/js) from being used in account names so an XSS is not possible.

Affected products

• miraheze GlobalNewFiles: before 2021-09-01 — fixed in 2021-09-01

How to fix

Upgrade to a fixed version: miraheze GlobalNewFiles 2021-09-01. Check the vendor advisory for mitigations.

References

• https://github.com/miraheze/GlobalNewFiles/commit/cee254e1b158cdb0ddbea716b1d3edc31fa4fb5d
• https://github.com/miraheze/GlobalNewFiles/security/advisories/GHSA-57p5-hqjq-h7vg
• https://phabricator.miraheze.org/T7935
• https://github.com/miraheze/GlobalNewFiles/commit/cee254e1b158cdb0ddbea716b1d3edc31fa4fb5d
• https://github.com/miraheze/GlobalNewFiles/security/advisories/GHSA-57p5-hqjq-h7vg
• https://phabricator.miraheze.org/T7935

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