Resource Exhaustion Affecting cpp-httplib package, versions <0.18.7-1+e1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-ECHOLATEST-CPPHTTPLIB-19401927
- published28 Aug 2026
- disclosed6 May 2025
Introduced: 6 May 2025
CVE-2025-46728 (opens in a new tab)How to fix?
Upgrade Echo:latest cpp-httplib to version 0.18.7-1+e1 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream cpp-httplib package and not the cpp-httplib package as distributed by Echo.
See How to fix? for Echo:latest relevant fixed versions and status.
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.