6.8
MEDIUM CVSS 4.0
CVE-2026-47075
CR/LF injection in query parameter in hackney
Description

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.

INFO

Published Date :

May 25, 2026, 2 p.m.

Last Modified :

May 25, 2026, 2 p.m.

Remotely Exploit :

No

Source :

EEF
Affected Products

The following products are affected by CVE-2026-47075 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 MEDIUM 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Solution
Update hackney to a version that properly encodes CRLF characters to prevent HTTP Request Splitting.
  • Update hackney to version 4.0.1 or later.
  • Ensure CRLF characters are percent-encoded in URLs.
  • Validate and escape URL query components.
  • Review HTTP request construction logic.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-47075 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-47075 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 6b3ad84c-e1a6-4bf7-a703-f496b71e49db

    May. 25, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V4.0 AV:L/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-93
    Added Reference https://cna.erlef.org/cves/CVE-2026-47075.html
    Added Reference https://github.com/benoitc/hackney/commit/ca73dd0aba0ed557449c18288bf07241671a43c9
    Added Reference https://github.com/benoitc/hackney/security/advisories/GHSA-j9wq-vxxc-94wf
    Added Reference https://osv.dev/vulnerability/EEF-CVE-2026-47075
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.