ID:12701 - Exploit for CRLF injection in Cpp-httplib - CVE-2026-45372

Link to public exploit:

Vulnerability description

The vulnerability allows a remote attacker to inject CRLF sequences into stored HTTP header values.

The vulnerability exists due to improper neutralization of CRLF sequences in the server-side parse_header function when parsing percent-encoded header values in incoming requests. A remote attacker can send a specially crafted request with encoded CRLF sequences to inject CRLF sequences into stored HTTP header values.

The issue can lead to inconsistent interpretation of header values by downstream application components, including response handling, logging, and proxying logic.

Remediation