CVE-2026-39839

Stored XSS through URLs in Cargo's map format

6.3 Medium

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.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: Low
User interaction: Passive

What an attacker can affect

Confidentiality: None
Integrity: None
Availability: None

Exploit likelihood

0.19%Up 0.1 points since Apr 8, 2026

What each source reports

CVE List Score used 6.3

Stored XSS through URLs in Cargo's map format

Record: CVE-2026-39839
CVSS 4.0: 6.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N
Weakness: CWE-80
Updated: 2026-11-02

EUVDEUVD-2026-19891 6.3

Record: EUVD-2026-19891
CVSS 4.0: 6.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N
Updated: 2026-11-02

GitHub AdvisoriesGHSA-r77j-8275-g6jm 6.3

Improper neutralization of Script-Related HTML tags in a web page (basic XSS) vulnerability in...

Record: GHSA-r77j-8275-g6jm
CVSS 4.0: 6.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1: 6.1 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weakness: CWE-80
Updated: 2026-11-02

NVD 6.3

Record: CVE-2026-39839
CVSS 4.0: 6.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1: 6.1 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weakness: CWE-80
Updated: 2026-11-02

Affected products

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, NVD

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-39839 is a medium vulnerability (CVSS 6.3) in Mediawiki Cargo, published April 7, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.19%, the 8th percentile. No source names a fixed version.