CVE-2026-29076
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.
- Affected products
- Cpp-Httplib
- Yhirose Cpp-httplib
- < 0.37.0
- Fix
- Available
- CVSS 3.1
- 5.9 MEDIUM
- EPSS
- 0.6% (45th percentile)
- Weakness
- CWE-674, CWE-1333
- NVD status
- Analyzed
- Published
- 2026-03-07
No indexed exploits for CVE-2026-29076 yet
Our index is partial: it proves presence, never absence
No exploit for CVE-2026-29076 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.