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.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/yhirose/cpp-httplib/commit/de296af3eb5b0d5c116470e033db900e4812c5e6	Patch
https://github.com/yhirose/cpp-httplib/releases/tag/v0.37.0	Product Release Notes
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-qq6v-r583-3h69	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:yhirose:cpp-httplib:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-07 16:15

Updated : 2026-03-09 21:19

NVD link : CVE-2026-29076

Mitre link : CVE-2026-29076

CVE.ORG link : CVE-2026-29076

JSON object : View

Products Affected

yhirose

cpp-httplib

CWE

CWE-674

Uncontrolled Recursion

CWE-1333

Inefficient Regular Expression Complexity

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