How serious is CVE-2026-29076?

This vulnerability has a CVSS score of 5.9 out of 10, classified as MEDIUM severity. No public exploit code has been identified yet.

Which products are affected by CVE-2026-29076?

CVE-2026-29076 affects yhirose cpp-httplib. Check the full CVE details for specific version information.

How do I fix CVE-2026-29076?

To remediate CVE-2026-29076, check for security patches from yhirose. Apply all available updates and security patches. If no patch is available, implement recommended workarounds or security controls to mitigate the risk.

CVE-2026-29076

Medium

|5.9

No Exploit

Plain English Summary

AI-powered analysis for quick understanding

An attacker can crash a server by sending a specially crafted HTTP POST request with a malicious filename in the multipart headers, which causes the server to run out of memory and stop working. This vulnerability affects versions prior to 0.37.0 of the cpp-httplib library, so updating to the latest version is essential to prevent this issue.

Technical Description

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 Vector Analysis

Attack VectorNetwork

Attack ComplexityHigh

Privileges RequiredNone

User InteractionNone

Confidentiality ImpactNone

Integrity ImpactNone

Availability ImpactHigh

ScopeUnchanged

Vector String

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploit Resources

Search for proof-of-concept code and exploit modules

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Official References

NIST NVD

Est. Bounty

$828($500-$1K)

Vendor Response

Grade APatched in 2 days

Quick Information

Published

Mar 7, 2026

about 1 month ago

Last Modified

Mar 9, 2026

29 days ago

Vendor

yhirose

Product

cpp-httplib