# CVE-2026-63686: Apache HTTP Server NULL pointer dereference in mod_xml2enc

Source: https://junglewise.ai/threats/cve-2026-63686-a-null-pointer-dereference-in-mod-xml2enc-in-apache-software  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-01. Updated: 2026-10-05  
License: CC BY 4.0 with a link back

CVE-2026-63686 · Severity: high · CVSS 7.5 · Published 2026-10-01

Apache HTTP Server is a web server that handles incoming web traffic and proxies requests to backend servers. A flaw in the mod_xml2enc module can crash the server when processing proxied responses with character encoding issues, allowing an untrusted backend server to trigger a denial of service and disrupt web services.

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

## Quick answers

**Is CVE-2026-63686 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-63686 being exploited in the wild.

**How severe is CVE-2026-63686?** High severity, with a CVSS score of 7.5, published 1 October 2026.

**Which products and versions are affected?** Apache Software Foundation HTTP Server 2.4.0 through 2.4.68.

**Is there a fix for CVE-2026-63686?** Yes: fixed in 2.4.69. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-63686 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-63686?** Check whether you run Apache Software Foundation HTTP Server at an affected version. 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.

## How to fix

- Fixed in 2.4.69

## Technical details

A NULL pointer dereference in mod_xml2enc occurs when processing a proxied response with a charset whose conversion partially succeeds then fails. The vulnerability is triggered by an untrusted backend server sending a malformed response, causing the server process to crash. This affects Apache HTTP Server 2.4.0 through 2.4.68 and is fixed in 2.4.69.

## Affected products

- Apache Software Foundation HTTP Server 2.4.0 through 2.4.68

## Timeline

- 2026-06-14: disclosed: Report received
- 2026-10-01: patched: Fixed in 2.4.x by r1938678; 2.4.69 released

## References

- [https://httpd.apache.org/security/vulnerabilities_24.html](https://httpd.apache.org/security/vulnerabilities_24.html)
- [http://www.openwall.com/lists/oss-security/2026/10/01/25](http://www.openwall.com/lists/oss-security/2026/10/01/25)

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