CVE-2026-28435: Yhirose Cpp-Httplib

High severity, CVSS 7.5. EPSS: 0.6% chance of exploitation in the next 30 days.

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.

Affected products

• Yhirose Cpp-Httplib: before 0.35.0 (fixed in 0.35.0)

Published 2026-03-04. Last modified 2026-06-17.