{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-47072", "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "state": "PUBLISHED", "assignerShortName": "EEF", "dateReserved": "2026-05-18T17:28:08.322Z", "datePublished": "2026-05-25T14:00:47.852Z", "dateUpdated": "2026-05-25T14:00:47.852Z"}, "containers": {"cna": {"affected": [{"collectionURL": "https://repo.hex.pm", "cpes": ["cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*"], "defaultStatus": "unaffected", "modules": ["hackney_ws"], "packageName": "hackney", "packageURL": "pkg:hex/hackney", "product": "hackney", "programFiles": ["src/hackney_ws.erl"], "programRoutines": [{"name": "hackney_ws:do_handshake/1"}, {"name": "hackney_ws:init/1"}], "repo": "https://github.com/benoitc/hackney", "vendor": "benoitc", "versions": [{"lessThan": "4.0.1", "status": "affected", "version": "2.0.0", "versionType": "semver"}]}, {"collectionURL": "https://github.com", "cpes": ["cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*"], "defaultStatus": "unaffected", "modules": ["hackney_ws"], "packageName": "benoitc/hackney", "packageURL": "pkg:github/benoitc/hackney", "product": "hackney", "programFiles": ["src/hackney_ws.erl"], "programRoutines": [{"name": "hackney_ws:do_handshake/1"}, {"name": "hackney_ws:init/1"}], "repo": "https://github.com/benoitc/hackney", "vendor": "benoitc", "versions": [{"lessThan": "52310ca807e7b48441ba0e9129171f535313fdd1", "status": "affected", "version": "690cecaf236fba49526da404a5bc889a24367a3e", "versionType": "git"}]}], "cpeApplicability": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*", "versionEndExcluding": "4.0.1", "versionStartIncluding": "2.0.0", "vulnerable": true}], "negate": false, "operator": "AND"}], "operator": "AND"}], "credits": [{"lang": "en", "type": "finder", "value": "Peter Ullrich"}, {"lang": "en", "type": "remediation developer", "value": "Benoit Chesneau"}, {"lang": "en", "type": "analyst", "value": "Jonatan M\u00e4nnchen"}], "descriptions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "Improper Neutralization of CRLF Sequences ('CRLF Injection') vulnerability in benoitc hackney allows HTTP Request/Response Splitting.<p>The WebSocket upgrade code in <tt>src/hackney_ws.erl</tt> copies the <tt>host</tt>, <tt>path</tt>, <tt>headers</tt> (ExtraHeaders), and <tt>protocols</tt> options from the caller-supplied opts map into the internal <tt>#ws_data{}</tt> record in <tt>init/1</tt> and then splices them verbatim into the raw HTTP/1.1 upgrade request by binary concatenation in <tt>do_handshake/1</tt>. No CRLF or NUL stripping is performed at any of these four injection sites. An attacker who controls any of these options \u2014 for example by forwarding URL components or header values from untrusted input into <tt>hackney_ws:start_link/1</tt> \u2014 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.</p><p>This issue affects hackney: from 2.0.0 before 4.0.1.</p>"}], "value": "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 \u2014 for example by forwarding URL components or header values from untrusted input into hackney_ws:start_link/1 \u2014 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.\n\nThis issue affects hackney: from 2.0.0 before 4.0.1."}], "impacts": [{"capecId": "CAPEC-33", "descriptions": [{"lang": "en", "value": "CAPEC-33 HTTP Request Smuggling"}]}], "metrics": [{"cvssV4_0": {"attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "baseScore": 6.9, "baseSeverity": "MEDIUM", "privilegesRequired": "NONE", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "HIGH", "userInteraction": "NONE", "vectorString": "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", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "LOW"}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"cweId": "CWE-93", "description": "CWE-93 Improper Neutralization of CRLF Sequences ('CRLF Injection')", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "shortName": "EEF", "dateUpdated": "2026-05-25T14:00:47.852Z"}, "references": [{"tags": ["vendor-advisory", "related"], "url": "https://github.com/benoitc/hackney/security/advisories/GHSA-f9vr-g2g2-x9fg"}, {"tags": ["related"], "url": "https://cna.erlef.org/cves/CVE-2026-47072.html"}, {"tags": ["related"], "url": "https://osv.dev/vulnerability/EEF-CVE-2026-47072"}, {"tags": ["patch"], "url": "https://github.com/benoitc/hackney/commit/52310ca807e7b48441ba0e9129171f535313fdd1"}], "source": {"discovery": "EXTERNAL"}, "title": "CRLF injection in WebSocket upgrade request in hackney", "x_generator": {"engine": "cvelib 1.8.0"}}}}

{}

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{"created": "2026-05-25T16:00:14.104699+00:00", "updated": "2026-05-25T16:00:14.104710+00:00", "vendors": []}