CVE-2026-28435

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.35.0, cpp-httplib (httplib.h) does not enforce Server::set_payload_max_length() on the decompressed request body when using HandlerWithContentReader (streaming ContentReader) with Content-Encoding: gzip (or other supported encodings). A small compressed payload can expand beyond the configured payload limit and be processed by the application, enabling a payload size limit bypass and potential denial of service (CPU/memory exhaustion). This vulnerability is fixed in 0.35.0.

Score

CVSS 3.1 7.5 High

Status

Analyzed - security-advisories@github.com

Published

2026-03-04

Last modified

2026-03-04

Weaknesses

CWE-400, CWE-409

Affected products

• Cpp-httplib (Yhirose)

References

• https://github.com/yhirose/cpp-httplib/commit/c99d7472b5cf4869d3897b9afc9792063a3d15a8
• https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-xvfx-w463-6fpp