CVE-2024-47840Public exploitNetwork attack vector

Stored XSS via unescaped sidebar values

Published Oct 5, 2024 · Updated Oct 7, 2024

Stored XSS in Wikimedia Foundation Apex allows remote attackers to execute script in visitors' browsers through crafted sidebar data. The skin inserts attacker-controlled MediaWiki:Sidebar values into sidebar HTML without sufficient output escaping, allowing stored markup to become executable script. Exploitation requires the ability to alter sidebar content, and the payload runs when visitors load pages using affected 1.39.x, 1.41.x, or 1.42.x branches.

CVSS severity6.9
Medium
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stored XSS in Wikimedia Foundation Apex allows remote attackers to execute script in visitors' browsers through crafted sidebar data. The skin inserts attacker-controlled MediaWiki:Sidebar values into sidebar HTML without sufficient output escaping, allowing stored markup to become executable script. Exploitation requires the ability to alter sidebar content, and the payload runs when visitors load pages using affected 1.39.x, 1.41.x, or 1.42.x branches.

The record

CVE
CVE-2024-47840
Published
Oct 5, 2024
Updated
Oct 7, 2024
Vendor
Wikimedia Foundation
Product
Apex
Classifications
CWE-79, CAPEC-592, T1059.007
Attack vector
network
Privileges
Unavailable

Timeline

How it unfolded

  1. Oct 5, 2024CVE publishedPublication date reported by the CVE source.
  2. Oct 7, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.39.0 <1.39.9
  2. Affected versionversion=1.39.x <1.39.9
  3. Affected versionversion=1.41.0 <1.41.3
  4. Affected versionversion=1.41.x <1.41.3
  5. Affected versionversion=1.42.0 <1.42.2
  6. Affected versionversion=1.42.x <1.42.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesUnavailable in this record.

What is affected?

Wikimedia Foundation · Apexversion=1.39.0 <1.39.9; version=1.39.x <1.39.9; version=1.41.0 <1.41.3; version=1.41.x <1.41.3; version=1.42.0 <1.42.2; version=1.42.x <1.42.2

Published CVSS scores

6.9Wikimedia FoundationCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
4.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CAPEC-592Stored XSS
T1059.007JavaScript/JScript

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo