Wikimedia Mediawiki up to 3.9.0 cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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4.1$0-$5k0.67-

Summaryinfo

A vulnerability was found in Wikimedia Mediawiki up to 3.9.0. It has been classified as problematic. Affected is an unknown function. This manipulation causes cross site scripting. This vulnerability is handled as CVE-2026-58519. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as problematic was found in Wikimedia Mediawiki up to 3.9.0. Affected by this vulnerability is an unknown code block. The manipulation with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. The summary by CVE is:

Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in The Wikimedia Foundation Mediawiki - Cargo Extension allows Stored XSS. This issue affects Mediawiki - Cargo Extension: from * before 3.9.1.

The weakness was released by SomeRandomDeveloper. The advisory is shared at phabricator.wikimedia.org. This vulnerability is known as CVE-2026-58519 since 07/01/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

It is declared as attacked.

Upgrading to version 3.9.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-40901). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Attacked

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Mediawiki 3.9.1

Timelineinfo

07/01/2026 Advisory disclosed
07/01/2026 +0 days CVE reserved
07/01/2026 +0 days VulDB entry created
07/01/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: phabricator.wikimedia.org
Researcher: SomeRandomDeveloper
Status: Confirmed

CVE: CVE-2026-58519 (🔒)
GCVE (CVE): GCVE-0-2026-58519
GCVE (VulDB): GCVE-100-375121
EUVD: 🔒

Entryinfo

Created: 07/01/2026 07:51
Updated: 07/01/2026 08:34
Changes: 07/01/2026 07:51 (69), 07/01/2026 08:34 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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