CVE-2026-29076: medium-severity vulnerability in yhirose cpp-httplib
cpp-httplib: Stack Overflow Denial of Service (DoS) via std::regex in multipart filename parsing
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.9epss 0.7%
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.37.0, cpp-httplib uses std::regex (libstdc++) to parse RFC 5987 encoded filename* values in multipart Content-Disposition headers. The regex engine in libstdc++ implements backtracking via deep recursion, consuming one stack frame per input character. An attacker can send a single HTTP POST request with a crafted filename* parameter that causes uncontrolled stack growth, resulting in a stack overflow (SIGSEGV) that crashes the server process. This issue has been patched in version 0.37.0.
CVSS:3.1/AV:N/AC:H/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-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%CVE-2026-28435HIGHPayload size limit bypass via gzip decompression in ContentReader (streaming) allows oversized request bodies in cpp-httplibEPSS 0.5%