CRLF injection in Cpp-httplib - CVE-2026-45372
Published: May 13, 2026
Vulnerability identifier: #VU131325
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/U:Green
CVE-ID: CVE-2026-45372
CWE-ID: CWE-93
Exploitation vector: Remote access
Exploit availability:
Public exploit is available
Vendor: Cpp-httplib Project
Affected software:
Cpp-httplib
Cpp-httplib
Detailed 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.
How to mitigate CVE-2026-45372
Install security update from vendor's website.