CVE-2025-52887: Yhirose Cpp-Httplib

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. In version 0.21.0, when many http headers fields are passed in, the library does not limit the number of headers, and the memory associated with the headers will not be released when the connection is disconnected. This leads to potential exhaustion of system memory and results in a server crash or unresponsiveness. Version 0.22.0 contains a patch for the issue.

Affected products

• Yhirose Cpp-Httplib: version 0.21.0 only

Published 2025-06-26. Last modified 2026-06-17.