CVE-2025-66577 – cpp-httplib Untrusted HTTP Header Handling: X-Forwarded-For/X-Real-IP Trust

CVE ID : CVE-2025-66577

Published : Dec. 5, 2025, 6:20 p.m. | 45 minutes ago

Description : 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.

Severity: 0.0 | NA

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