CVE-2025-66577 - CVE House
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Status published Medium CVE-2025-66577

cpp-httplib Untrusted HTTP Header Handling: X-Forwarded-For/X-Real-IP Trust

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

cpp-httplib
Vulnerable Versions:
< 0.27.0

Timeline

Official Publish: December 5th, 2025
Last Modified: December 5th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Weaknesses (CWE)

CWE-117 CWE-807

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.