CVE-2026-39935 | BDVDB-2026-325440 Detail

The Wikimedia FoundationMediawiki - CampaignEvents Extension

Description#

Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in The Wikimedia Foundation Mediawiki - CampaignEvents Extension allows Cross-Site Scripting (XSS). This issue was remediated only on the `master` branch.

Impact#

CAPEC-63 Cross-Site Scripting (XSS)

Weaknesses#

CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

References#

Exploit#

No public exploit known

History#

Version 12026-04-07Record published in the CVE List.
Version 22026-04-08Most recent update recorded in the CVE List.

Published

Published: 2026-04-07
Last modified: 2026-04-08

Vendor information

Vendor: The Wikimedia Foundation
Product: Mediawiki - CampaignEvents Extension

All The Wikimedia Foundation vulnerabilities

Score

6.9 Medium

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 20.4.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Cross-Site Scripting

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
1.43
Fixed
Not stated
Vulnerable
1.44
Fixed
Not stated
Vulnerable
1.45
Fixed
Not stated
Vulnerable
< 1.43
Fixed
1.43

Scoring System

CVSS v4.0

6.9 Medium

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L

Metric breakdown
Attack Vector	Network
Attack Complexity	Low
Attack Requirements	None
Privileges Required	None
User Interaction	None
Vulnerable System Confidentiality	Low
Vulnerable System Integrity	Low
Vulnerable System Availability	Low
Subsequent System Confidentiality	Low
Subsequent System Integrity	Low
Subsequent System Availability	Low

CVSS v3.1

Not available

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).