{"timestamp":"2026-05-26T15:46:12.092004Z","id":"CVE-2026-47072","options":[{"exploitation":"poc"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}

[{"vendor":"benoitc","product":"hackney","defaultStatus":"unaffected","collectionURL":"https://repo.hex.pm","packageName":"hackney","cpes":["cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*"],"modules":["hackney_ws"],"programFiles":["src/hackney_ws.erl"],"programRoutines":[{"name":"hackney_ws:do_handshake/1"},{"name":"hackney_ws:init/1"}],"repo":"https://github.com/benoitc/hackney","packageURL":"pkg:hex/hackney","versions":[{"version":"2.0.0","lessThan":"4.0.1","versionType":"semver","status":"affected"}]},{"vendor":"benoitc","product":"hackney","defaultStatus":"unaffected","collectionURL":"https://github.com","packageName":"benoitc/hackney","cpes":["cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*"],"modules":["hackney_ws"],"programFiles":["src/hackney_ws.erl"],"programRoutines":[{"name":"hackney_ws:do_handshake/1"},{"name":"hackney_ws:init/1"}],"repo":"https://github.com/benoitc/hackney","packageURL":"pkg:github/benoitc/hackney","versions":[{"version":"690cecaf236fba49526da404a5bc889a24367a3e","lessThan":"52310ca807e7b48441ba0e9129171f535313fdd1","versionType":"git","status":"affected"}]}]

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

OR
          *cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:* versions from (including) 2.0.0 up to (excluding) 4.0.1

CISA-ADP: https://github.com/benoitc/hackney/security/advisories/GHSA-f9vr-g2g2-x9fg Types: Exploit, Patch, Vendor Advisory

EEF: https://cna.erlef.org/cves/CVE-2026-47072.html Types: Patch, Third Party Advisory

EEF: https://github.com/benoitc/hackney/commit/52310ca807e7b48441ba0e9129171f535313fdd1 Types: Patch

EEF: https://github.com/benoitc/hackney/security/advisories/GHSA-f9vr-g2g2-x9fg Types: Exploit, Patch, Vendor Advisory

EEF: https://osv.dev/vulnerability/EEF-CVE-2026-47072 Types: Patch, Third Party Advisory

https://github.com/benoitc/hackney/security/advisories/GHSA-f9vr-g2g2-x9fg

Improper Neutralization of CRLF Sequences ('CRLF Injection') vulnerability in benoitc hackney allows HTTP Request/Response Splitting. The WebSocket upgrade code in src/hackney_ws.erl copies the host, path, headers (ExtraHeaders), and protocols options from the caller-supplied opts map into the internal #ws_data{} record in init/1 and then splices them verbatim into the raw HTTP/1.1 upgrade request by binary concatenation in do_handshake/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 hackney_ws: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.

AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/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

CWE-93

https://cna.erlef.org/cves/CVE-2026-47072.html

https://github.com/benoitc/hackney/commit/52310ca807e7b48441ba0e9129171f535313fdd1

https://github.com/benoitc/hackney/security/advisories/GHSA-f9vr-g2g2-x9fg

https://osv.dev/vulnerability/EEF-CVE-2026-47072