CVE-2025-66577

MEDIUM

cpp-httplib <0.27.0 - Log Poisoning

Title source: llm

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.

Scores

CVSS v3 5.3
EPSS 0.0007
EPSS Percentile 21.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Classification

CWE
CWE-807 CWE-117
Status published

Affected Products (1)

yhirose/cpp-httplib < 0.27.0

Timeline

Published Dec 05, 2025
Tracked Since Feb 18, 2026