Resource exhaustion in Yhirose Cpp-Httplib
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.
Vulnerability class: DoS (Denial of Service)
EPSS: 0.004 (34.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Yhirose Cpp-httplib — versions < 0.35.0
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Mitigation, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-28435?
- CVE-2026-28435 is a high-severity vulnerability in Yhirose Cpp-Httplib, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-03-04.
- How severe is CVE-2026-28435?
- High severity. CVSS v3 base score is 7.5 out of 10.