# CVE-2026-115825: HTTP::Server::PSGI memory exhaustion via large Content-Length

Source: https://junglewise.ai/threats/cve-2026-115825-http-server-psgi-versions-before-1-0056-for-perl-allow-a-single  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-25. Updated: 2026-10-25  
License: CC BY 4.0 with a link back

CVE-2026-115825 · Severity: info · Published 2026-10-25

HTTP::Server::PSGI is a Perl-based web server commonly used for PSGI applications. A remote attacker can send a single HTTP request declaring an extremely large Content-Length header with minimal body data, causing the server to attempt a massive memory allocation and crash with an out-of-memory error. Since the server runs as a single process, it remains offline until manually restarted.

Vendors: [CPAN](https://junglewise.ai/threats/vendors/cpan).

## Quick answers

**Is CVE-2026-115825 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-115825 being exploited in the wild.

**How severe is CVE-2026-115825?** Informational severity, published 25 October 2026.

**Which products and versions are affected?** CPAN HTTP::Server::PSGI before 1.0056.

**Is there a fix for CVE-2026-115825?** Yes: fixed in HTTP::Server::PSGI 1.0056. Until then: Restrict the maximum Content-Length header that the server will accept, or place HTTP::Server::PSGI behind a reverse proxy or load balancer that enforces reasonable request size limits. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-115825 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-115825?** Check whether you run CPAN HTTP::Server::PSGI 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 HTTP::Server::PSGI 1.0056

Restrict the maximum Content-Length header that the server will accept, or place HTTP::Server::PSGI behind a reverse proxy or load balancer that enforces reasonable request size limits.

## Technical details

HTTP::Server::PSGI's sysread() call passes the full remaining Content-Length as the read size parameter; Perl pre-allocates the read buffer to this size before any data arrives, allowing an attacker to force unbounded memory allocation. A remote unauthenticated attacker can crash the server with a single malformed HTTP request by declaring a Content-Length in the gigabyte range. The fix caps body reads at 64 KiB chunks, preventing excessive buffer allocation.

## Affected products

- CPAN HTTP::Server::PSGI before 1.0056

## Timeline

- 2026-10-25: disclosed
- 2026-10-23: patched: Patch released prior to public disclosure

## References

- [https://cpan.org/modules](https://cpan.org/modules)
- [https://github.com/plack/Plack/commit/11545871cadc5df1b744cebb429cfeb4ebc1069a.patch](https://github.com/plack/Plack/commit/11545871cadc5df1b744cebb429cfeb4ebc1069a.patch)