CVE-2026-28435: high-severity vulnerability in yhirose cpp-httplib
Payload size limit bypass via gzip decompression in ContentReader (streaming) allows oversized request bodies in cpp-httplib
Published
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.5%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
yhirose · cpp-httplibRelated CVEs — yhirose cpp-httplib
In the same product, most dangerous first.
CVE-2026-29076MEDIUMcpp-httplib: Stack Overflow Denial of Service (DoS) via std::regex in multipart filename parsingEPSS 0.7%CVE-2025-46728HIGHcpp-httplib has Unbounded Memory Allocation in Chunked/No-Length RequestsEPSS 0.7%CVE-2025-53629HIGHcpp-httplib Unbounded Memory Allocation in Chunked/No-Length Requests VulnerabilityEPSS 0.6%CVE-2025-53628MEDIUMcpp-httplib does not limit the length of a lineEPSS 0.5%CVE-2026-31870HIGHcpp-httplib Affected by Remote Process Crash via Malformed Content-Length Response HeaderEPSS 0.5%CVE-2025-52887HIGHcpp-httplib has unlimited number of http header fields, which causes memory leakEPSS 0.5%