HOMEVULNERABILITIESCVE-2026-39840
MEDIUM

CVE-2026-39840

CWE-79Published: April 7, 2026· Updated: Apr 8, 2026

5.1
CVSS v3.1
EPSS:0.05%probability of exploitation in 30 daysPercentile:14.4th

Official Description

Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Wikimedia Foundation Mediawiki - Cargo Extension allows XSS Targeting Non-Script Elements.This issue affects Mediawiki - Cargo Extension: before 3.8.7.

NVD Source

Technical Analysis

CVE-2026-39840 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.Low
User InteractionP
ScopeX
Impact
Confidentiality
Integrity
Availability
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/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

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
External links open in a new tab. Always verify in a controlled environment before use.

All References (2)

Quick Facts

CVE IDCVE-2026-39840
CVSS Score5.1 / 10
SeverityMEDIUM
WeaknessCWE-79
CISA KEVNo
EPSS (30d)0.05%
PublishedApr 7, 2026

Related CVEs (CWE-79)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2026-39840 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.