# CVE-2026-57941: Apache HTTP Server mod_http2 use-after-free via shared session bbtmp

Source: https://junglewise.ai/threats/cve-2026-57941-use-after-free-vulnerability-in-apache-http-server-s-mod-http2  
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-2026-57941 · Severity: critical · CVSS 9.8 · Published 2026-10-01

Apache HTTP Server is a widely used web server that handles requests from clients across the internet. A use-after-free vulnerability in the HTTP/2 module allows attackers to manipulate shared session memory through re-entrancy, potentially causing server crashes or arbitrary code execution. This could lead to denial of service or compromise of web server integrity.

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

## Quick answers

**Is CVE-2026-57941 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-57941 being exploited in the wild.

**How severe is CVE-2026-57941?** Critical severity, with a CVSS score of 9.8, published 1 October 2026.

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

**Is there a fix for CVE-2026-57941?** Yes: fixed in Apache HTTP Server 2.4.69. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-57941 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-57941?** Check whether you run Apache 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 Apache HTTP Server 2.4.69

## Technical details

A use-after-free vulnerability exists in mod_http2 due to improper handling of shared session->bbtmp buffers during re-entrant operations. The vulnerability affects Apache HTTP Server 2.4.0 through 2.4.68 and can be triggered remotely over the network without authentication. Exploitation could result in memory corruption, denial of service, or remote code execution.

## Affected products

- Apache HTTP Server 2.4.0 through 2.4.68

## Timeline

- 2026-06-15: disclosed
- 2026-10-01: patched: fixed in 2.4.x by r1938665
- 2026-10-01: advisory: 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/2026/10/01/19](http://www.openwall.com/lists/oss-security/2026/10/01/19)

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