CVE-2025-66577 — cpp-httplib Untrusted HTTP Header Handling: X-Forwarded-For/X-Real-IP Trust
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.27.0, a vulnerability allows attacker-controlled HTTP headers to influence server-vi…
Published: 2025-12-05 · CVSS: 5.3 · CVSS 3.1
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.27.0, a vulnerability allows attacker-controlled HTTP headers to influence server-visible metadata, logging, and authorization decisions. An attacker can supply X-Forwarded-For or X-Real-IP headers which get accepted unconditionally by get_client_ip() in docker/main.cc, causing access and error logs (nginx_access_logger / nginx_error_logger) to record spoofed client IPs (log poisoning / audit evasion). This vulnerability is fixed in 0.27.0.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7