PT-2026-43066 · Benoitc · Hackney

Benoit Chesneau + 2 · Published 2026-05-25 · Updated 2026-05-25 · CVE-2026-47069

Mitre

CVSS v4.0

2.1

Low

Base vector

AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N

Improper Neutralization of CRLF Sequences ('CRLF Injection') vulnerability in benoitc hackney allows HTTP Response Splitting. The hackney cookie:setcookie/3 function in src/hackney cookie.erl validates the Name and Value arguments against CRLF and control characters, but concatenates the domain and path options verbatim into the output iolist with no equivalent check. An attacker who controls either option — for example by supplying a Host header value forwarded as the cookie domain, or a request path forwarded as the cookie path — can inject a literal CRLF sequence and arbitrary additional Set-Cookie headers into the HTTP response.

This issue affects hackney: from 0.9.0 before 4.0.1.

Fix

Weakness Enumeration

CWE-93

Related Identifiers

CVE-2026-47069

Affected Products

Hackney

References · 4

• https://github.com/benoitc/hackney/security/advisories/GHSA-mp55-p8c9-rfw2 · Vendor Advisory
• https://github.com/benoitc/hackney/commit/8e02b99c28aea1b3fa2ddc0e66f51fe5bb0ac540 · Patch
• https://cna.erlef.org/cves/CVE-2026-47069.html · Note
• https://osv.dev/vulnerability/EEF-CVE-2026-47069 · Note