Vulnerability Description
cpp-httplib is a C++ header-only HTTP/HTTPS server and client library. Prior to version 0.20.1, the library fails to enforce configured size limits on incoming request bodies when `Transfer-Encoding: chunked` is used or when no `Content-Length` header is provided. A remote attacker can send a chunked request without the terminating zero-length chunk, causing uncontrolled memory allocation on the server. This leads to potential exhaustion of system memory and results in a server crash or unresponsiveness. Version 0.20.1 fixes the issue by enforcing limits during parsing. If the limit is exceeded at any point during reading, the connection is terminated immediately. A short-term workaround through a Reverse Proxy is available. If updating the library immediately is not feasible, deploy a reverse proxy (e.g., Nginx, HAProxy) in front of the `cpp-httplib` application. Configure the proxy to enforce maximum request body size limits, thereby stopping excessively large requests before they reach the vulnerable library code.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Cpp-Httplib Project | Cpp-Httplib | < 0.20.1 |
Related Weaknesses (CWE)
References
- https://github.com/yhirose/cpp-httplib/commit/7b752106ac42bd5b907793950d9125a097Patch
- https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-px83-72rx-v57cExploitVendor Advisory
FAQ
What is CVE-2025-46728?
CVE-2025-46728 is a vulnerability with a CVSS score of 7.5 (HIGH). cpp-httplib is a C++ header-only HTTP/HTTPS server and client library. Prior to version 0.20.1, the library fails to enforce configured size limits on incoming request bodies when `Transfer-Encoding: ...
How severe is CVE-2025-46728?
CVE-2025-46728 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-46728?
Check the references section above for vendor advisories and patch information. Affected products include: Cpp-Httplib Project Cpp-Httplib.