Wikimedia Cargo Extension up to 3.8.6 on Mediawiki cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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3.4$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic has been found in Wikimedia Cargo Extension up to 3.8.6 on Mediawiki. Affected by this vulnerability is an unknown functionality. The manipulation leads to cross site scripting. This vulnerability is traded as CVE-2026-39841. It is possible to initiate the attack remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Wikimedia Cargo Extension up to 3.8.6 on Mediawiki. It has been rated as problematic. This issue affects some unknown processing. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-80. The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as "<", ">", and "&" that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages. Impacted is integrity. The summary by CVE is:

Improper neutralization of Script-Related HTML tags in a web page (basic XSS) vulnerability in Wikimedia Foundation Mediawiki - Cargo Extension allows Stored XSS.This issue affects Mediawiki - Cargo Extension: before 3.8.7.

The weakness was shared by Alex44019. The advisory is shared at phabricator.wikimedia.org. The identification of this vulnerability is CVE-2026-39841 since 04/07/2026. The exploitation is known to be easy. The attack may be initiated remotely. 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.

Upgrading to version 3.8.7 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-19931). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

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: 3.5
VulDB Meta Temp Score: 3.4

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Cross site scripting
CWE: CWE-80 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

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: Cargo Extension 3.8.7

Timelineinfo

04/07/2026 Advisory disclosed
04/07/2026 +0 days CVE reserved
04/07/2026 +0 days VulDB entry created
04/07/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: phabricator.wikimedia.org
Researcher: Alex44019
Status: Confirmed

CVE: CVE-2026-39841 (🔒)
GCVE (CVE): GCVE-0-2026-39841
GCVE (VulDB): GCVE-100-355949
EUVD: 🔒

Entryinfo

Created: 04/07/2026 23:32
Updated: 04/07/2026 23:45
Changes: 04/07/2026 23:32 (69), 04/07/2026 23:45 (1)
Complete: 🔍
Cache ID: 216:E82:103

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