# CVE-2021-42013: Apache HTTP Server Path Traversal Vulnerability

Source: https://junglewise.ai/threats/cve-2021-42013-apache-http-server-path-traversal-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-11-03. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2021-42013 · Severity: critical · CVSS 9.8 · Exploited in the wild · Published 2021-11-03

An incomplete patch for CVE-2021-41773 in Apache HTTP Server 2.4.50 allows for path traversal and potential remote code execution. Attackers can map URLs to files outside the document root if Alias-like directives are used without 'require all denied' protections, or execute arbitrary code if CGI scripts are enabled.

Technologies: [Apache HTTP Server](https://junglewise.ai/threats/technologies/http-server). Vendors: [Apache](https://junglewise.ai/threats/vendors/apache).

## Quick answers

**Is CVE-2021-42013 exploited in the wild?** Yes. CVE-2021-42013 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

**How severe is CVE-2021-42013?** Critical severity, with a CVSS score of 9.8, published 3 November 2021.

**Which products and versions are affected?** Apache HTTP Server 2.4.49, 2.4.50.

**Is there a fix for CVE-2021-42013?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2021-42013 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2021-42013?** Check whether you run Apache HTTP Server. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Apache HTTP Server 2.4.49, 2.4.50

## Timeline

- 2021-11-03: disclosed
- 2021-11-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
- 2021-11-03: advisory: NVD publication date

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