CVE-2026-47075
HighSummary
The vulnerability related to improper neutralization of CRLF sequences in the hackney library allows HTTP request splitting. Hackney does not percent-encode carriage return ( ) or line feed ( ) characters in the URL query component before constructing the HTTP/1.1 request target.
Risk Assessment
Attackers can inject raw CRLF sequences into the query string, enabling the injection of arbitrary HTTP headers or splitting of the HTTP request. This can lead to serious security issues for the application.
Recommendation
It is recommended to update the hackney library to version 4.0.1 or later to mitigate this vulnerability. Additionally, a code audit should be conducted to ensure proper URL validation and encoding.
Original NVD description (English source)
Improper Neutralization of CRLF Sequences vulnerability in benoitc hackney allows HTTP Request Splitting. hackney does not percent-encode carriage return (\r) or line feed (\n) characters in the URL query component before constructing the HTTP/1.1 request target. Characters outside the grammar defined in RFC 3986 Section 3.4 must be percent-encoded, but hackney_url:make_url/3 passes the query binary directly without validation or escaping. An attacker who can control all or part of a URL passed to hackney can inject raw CRLF sequences into the query string, which are then sent as HTTP line breaks in the request target. This enables injection of arbitrary HTTP headers or splitting of the HTTP request. This issue affects hackney: from 0 before 4.0.1.