EEF-CVE-2026-47072

Source
https://cna.erlef.org/osv/EEF-CVE-2026-47072.html
Import Source
https://cna.erlef.org/osv/EEF-CVE-2026-47072.json
JSON Data
https://api.osv.dev/v1/vulns/EEF-CVE-2026-47072
Aliases
  • CVE-2026-47072
  • GHSA-f9vr-g2g2-x9fg
Published
2026-05-25T14:00:47.852Z
Modified
2026-05-25T14:26:25.323416700Z
Severity
  • 6.9 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:H/SA:N CVSS Calculator
Summary
CRLF injection in WebSocket upgrade request in hackney
Details

Summary

Improper Neutralization of CRLF Sequences ('CRLF Injection') vulnerability in benoitc hackney allows HTTP Request/Response Splitting. The WebSocket upgrade code in src/hackneyws.erl copies the host, path, headers (ExtraHeaders), and protocols options from the caller-supplied opts map into the internal #wsdata{} record in init/1 and then splices them verbatim into the raw HTTP/1.1 upgrade request by binary concatenation in dohandshake/1. No CRLF or NUL stripping is performed at any of these four injection sites. An attacker who controls any of these options — for example by forwarding URL components or header values from untrusted input into hackneyws:start_link/1 — can inject arbitrary HTTP headers into the outbound WebSocket upgrade request, leading to header injection, credential spoofing toward the upstream server, log and cache poisoning, or request smuggling via intermediary proxies.

This issue affects hackney: from 2.0.0 before 4.0.1.

Database specific
{
    "cpe_ids": [
        "cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*"
    ],
    "cwe_ids": [
        "CWE-93"
    ],
    "capec_ids": [
        "CAPEC-33"
    ]
}
References
Credits
    • Peter Ullrich - FINDER
    • Benoit Chesneau - REMEDIATION_DEVELOPER
    • Jonatan Männchen - ANALYST

Affected packages

Hex / hackney

Package

Name
hackney
Purl
pkg:hex/hackney

Affected ranges

Type
SEMVER
Events
Introduced
2.0.0
Fixed
4.0.1

Affected versions

2.*
2.0.0
2.0.1
3.*
3.0.0
3.0.1
3.0.2
3.0.3
3.1.0
3.1.1
3.1.2
3.2.0
3.2.1
4.*
4.0.0

Database specific

source
"https://cna.erlef.org/osv/EEF-CVE-2026-47072.json"

Git / github.com/benoitc/hackney

Affected ranges

Type
GIT
Repo
https://github.com/benoitc/hackney
Events

Database specific

source
"https://cna.erlef.org/osv/EEF-CVE-2026-47072.json"