CVE-2020-26121
mediumpriority · track · 30OT risk · elevatedEPSS 0.013 · 70 %ileEUUSEPSS · scored 2026-10-27
An issue was discovered in the FileImporter extension for MediaWiki before 1.34.4. An attacker can import a file even when the target page is protected against "page creation" and the attacker should not be able to create it. This occurs because of a mishandled distinction between an upload restriction and a create restriction. An attacker cannot leverage this to overwrite anything, but can leverage this to force a wiki to have a page with a disallowed title.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- BIT-mediawiki-2020-261212024-03-06vendor · osvUS
An issue was discovered in the FileImporter extension for MediaWiki before 1.34.4. An attacker can import a file even when the target page is protected against "page creation" and the attacker should not be able to create it. This occurs because of a mishandled distinction between an upload restriction and a create restriction. An attacker cannot leverage this to overwrite anything, but can leverage this to force a wiki to have a page with a disallowed title.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (14)
External citations — patches, advisories, analysis.
- https://commons.wikimedia.org/w/index.php?oldid=454609892#File:Wiki.pngcnnvd
- https://gerrit.wikimedia.org/r/q/Ib852a96afc4dca10516d0510e69c10f9892b351bcnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RTTPZ7XMDS66I442OLLHXBDNP2LCBJU6/cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2020-26121cnnvd
- https://phabricator.wikimedia.org/T262628cnnvd
- https://vigilance.fr/vulnerability/MediaWiki-spoofing-via-FileImporter-Extension-34103cnnvd
- https://commons.wikimedia.org/w/index.php?oldid=454609892#File:Wiki.pngenisa_euvd
- https://gerrit.wikimedia.org/r/q/Ib852a96afc4dca10516d0510e69c10f9892b351benisa_euvd
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