# CVE-2026-58035: Wikimedia Foundation MediaWiki XSS in SpecialBlock.Vue

Source: https://junglewise.ai/threats/cve-2026-58035-wikimedia-foundation-mediawiki-xss-in-specialblock-vue  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-01. Updated: 2026-07-01  
License: CC BY 4.0 with a link back

CVE-2026-58035 · Severity: info · CVSS 0 · Published 2026-07-01

MediaWiki, the software powering Wikipedia and many other wikis, contains a security flaw in its user blocking interface. An attacker with high-level administrative privileges could potentially execute malicious scripts in the browser of another user. While the risk is limited by the high level of access required, it could lead to unauthorized actions being performed on behalf of other administrators.

Technologies: [Wikimedia Foundation MediaWiki](https://junglewise.ai/threats/technologies/mediawiki). Vendors: [Wikimedia Foundation](https://junglewise.ai/threats/vendors/wikimedia-foundation).

## Quick answers

**Is CVE-2026-58035 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-58035 being exploited in the wild.

**How severe is CVE-2026-58035?** Informational severity, with a CVSS score of 0, published 1 July 2026.

**Which products and versions are affected?** Wikimedia Foundation MediaWiki 1.46.0-rc.0 to 1.46.0.

**Is there a fix for CVE-2026-58035?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-58035 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-58035?** Check whether you run Wikimedia Foundation MediaWiki at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A Cross-site Scripting (XSS) vulnerability exists in MediaWiki within the SpecialBlock.Vue component (resources/src/mediawiki.Special.Block/SpecialBlock.Vue). The flaw stems from improper neutralization of input during web page generation. An attacker with high privileges (PR:H) can exploit this over the network, though it requires some level of user interaction (UI:P). Successful exploitation allows the execution of arbitrary JavaScript in the context of the victim's browser session. The vulnerability affects versions starting from 1.46.0-rc.0 and is addressed in version 1.46.0.

## Affected products

- Wikimedia Foundation MediaWiki 1.46.0-rc.0 to 1.46.0

## Timeline

- 2026-07-01: advisory: CVE-2026-58035 published by Wikimedia Foundation

## References

- [https://phabricator.wikimedia.org/T428809](https://phabricator.wikimedia.org/T428809)

## Related threats

- [Mediawiki Wikibase Extension stored cross-site scripting](https://junglewise.ai/threats/cve-2026-100245-improper-neutralization-of-input-during-web-page-generation-xss)
- [Wikimedia Mediawiki UploadWizard DOM XSS in Flickr titles](https://junglewise.ai/threats/cve-2026-100381-improper-neutralization-of-input-during-web-page-generation-xss)
- [MediaWiki Wikibase reflected XSS in Special:SetLabel](https://junglewise.ai/threats/cve-2026-100380-improper-neutralization-of-input-during-web-page-generation-xss)
- [Wikimedia Foundation MediaWiki XSS in Logging and Special Pages](https://junglewise.ai/threats/cve-2026-58037-wikimedia-foundation-mediawiki-xss-in-logging-and-special-pages)
- [Wikimedia Foundation MediaWiki Information Exposure in User API](https://junglewise.ai/threats/cve-2026-58036-wikimedia-foundation-mediawiki-information-exposure-in-user-api)