Exposure of Sensitive Information to an Unauthorized Actor vulnerability in Wikimedia Foundation MediaWiki. (CVE-2026-58036)
Description
A vulnerability in Wikimedia Foundation MediaWiki allows exposure of sensitive information to unauthorized actors. The issue involves several program files related to API queries and permission management. It has a CVSS score of 7.5, indicating a medium severity level. The vulnerability affects multiple specific versions of MediaWiki, including various Ubuntu package versions. No known exploits are reported in the wild, and no patch or remediation details are provided in the available data.
CVSS v3.1
Score 7.5high
Affected software
pkg:deb/ubuntu/mediawiki?arch=source&distro=bionicpkg:deb/ubuntu/mediawiki?arch=source&distro=esm-apps/focalpkg:deb/ubuntu/mediawiki?arch=source&distro=esm-apps/jammypkg:deb/ubuntu/mediawiki?arch=source&distro=esm-apps/noblepkg:deb/ubuntu/mediawiki?arch=source&distro=questingpkg:deb/ubuntu/mediawiki?arch=source&distro=stonkingpkg:deb/ubuntu/mediawiki?arch=source&distro=resoluteRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-58036 is an information exposure vulnerability in Wikimedia Foundation MediaWiki. It involves unauthorized disclosure of sensitive information through components such as includes/Api/ApiQueryAllUsers.Php, includes/Api/ApiQueryUsers.Php, includes/Permissions/PermissionManager.Php, and includes/User/UserGroupManager.Php. The vulnerability is rated medium severity with a CVSS 3.1 score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N), indicating network attack vector, low attack complexity, no privileges or user interaction required, and high confidentiality impact without integrity or availability impact. Multiple specific versions of MediaWiki, including Ubuntu package variants, are affected. There is no information on available patches or vendor advisories in the provided data.
Potential Impact
The vulnerability allows an attacker with network access to obtain sensitive information from the MediaWiki installation without requiring privileges or user interaction. The confidentiality impact is high, but integrity and availability are not affected. This could lead to unauthorized disclosure of sensitive data managed by MediaWiki.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no patch or official fix information is provided, users should monitor official Wikimedia Foundation and Ubuntu security advisories for updates. Until a fix is available, restrict network access to the affected MediaWiki instances where possible.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- UBUNTU-CVE-2026-58036
- Osv Schema Version
- 1.7.0
- Ecosystems
- ["Ubuntu:18.04:LTS","Ubuntu:Pro:20.04:LTS","Ubuntu:Pro:22.04:LTS","Ubuntu:Pro:24.04:LTS","Ubuntu:25.10","Ubuntu:26.10","Ubuntu:26.04:LTS"]
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6ad3f5de2cdf04f656663477
Added to database: 10/17/2026, 22:25:34 UTC
Last enriched: 10/18/2026, 00:33:07 UTC
Last updated: 10/18/2026, 00:33:07 UTC
Views: 2
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