CVE-2026-47075CWE-93

CR/LF injection in query parameter in hackney

Medium · published May 25, 2026

CVSS v4.0
6.8
EPSS
0%
Percentile
35.5
In the wild
Unconfirmed
What it is

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 0.13.1 before 4.0.1.

The record
Technical detail
CVSS v4.0
6.8 · MEDIUM
Vector
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N
EPSS
0.00422 · 35.5th percentile
Weakness
CWE-93 · Improper Neutralization of CRLF Sequences ('CRLF Injection')
Published
2026-05-25T14:00Z
EPSS history
Timeline
  • 25 MAY 14:00Z
    CR/LF injection in query parameter in hackney
    cvelistv5