Improper Output Neutralization for Logs Affecting cpp-httplib package, versions *
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-DEBIAN12-CPPHTTPLIB-14193178
- published6 Dec 2025
- disclosed5 Dec 2025
Introduced: 5 Dec 2025
NewCVE-2025-66577 (opens in a new tab)How to fix?
There is no fixed version for Debian:12 cpp-httplib.
NVD Description
Note: Versions mentioned in the description apply only to the upstream cpp-httplib package and not the cpp-httplib package as distributed by Debian.
See How to fix? for Debian:12 relevant fixed versions and status.
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.