{"id":"CVE-2026-1527","details":"ImpactWhen an application passes user-controlled input to the upgrade option of client.request(), an attacker can inject CRLF sequences (\\r\\n) to:\n\n  *  Inject arbitrary HTTP headers\n  *  Terminate the HTTP request prematurely and smuggle raw data to non-HTTP services (Redis, Memcached, Elasticsearch)\nThe vulnerability exists because undici writes the upgrade value directly to the socket without validating for invalid header characters:\n\n// lib/dispatcher/client-h1.js:1121\nif (upgrade) {\n  header += `connection: upgrade\\r\\nupgrade: ${upgrade}\\r\\n`\n}","aliases":["GHSA-4992-7rv2-5pvq"],"modified":"2026-04-17T13:29:24.460963672Z","published":"2026-03-12T21:16:25.137Z","related":["ALSA-2026:7350","ALSA-2026:7670","ALSA-2026:7675","CGA-474r-8wcx-87w5"],"references":[{"type":"ADVISORY","url":"https://cna.openjsf.org/security-advisories.html"},{"type":"REPORT","url":"https://hackerone.com/reports/3487198"},{"type":"FIX","url":"https://github.com/nodejs/undici/security/advisories/GHSA-4992-7rv2-5pvq"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/nodejs/undici","events":[{"introduced":"0"},{"fixed":"8873c947271faf1ebc455bdc6158ecbc022ecfa9"},{"introduced":"1cfe0949053aac6267f11b919cee9315a27f1fd6"},{"fixed":"07a39067a0485c1953196f500d945fe09378a176"}],"database_specific":{"versions":[{"introduced":"0"},{"fixed":"6.24.0"},{"introduced":"7.0.0"},{"fixed":"7.24.0"}]}}],"versions":["v1.0.0","v1.0.1","v1.0.2","v1.0.3","v1.1.0","v1.2.0","v1.2.1","v1.2.2","v1.2.5","v1.2.6","v1.3.0","v1.3.1","v2.0.0","v2.0.1","v2.0.2","v2.0.3","v2.0.4","v2.0.5","v2.0.6","v2.0.7","v2.1.0","v3.0.0","v3.1.0","v3.2.0","v3.3.0","v3.3.1","v4.0.0","v4.0.0-alpha.0","v4.0.0-alpha.1","v4.0.0-alpha.2","v4.0.0-alpha.4","v4.0.0-alpha.5","v4.0.0-rc.1","v4.0.0-rc.2","v4.0.0-rc.3","v4.0.0-rc.4","v4.0.0-rc.5","v4.0.0-rc.7","v4.0.0-rc.8","v4.1.0","v4.1.1","v4.10.0","v4.10.1","v4.10.2","v4.10.3","v4.10.4","v4.11.0","v4.11.1","v4.11.2","v4.11.3","v4.12.0","v4.12.2","v4.13.0","v4.14.0","v4.14.1","v4.15.0","v4.15.1","v4.16.0","v4.2.1","v4.2.2","v4.3.0","v4.3.1","v4.4.1","v4.4.2","v4.4.3","v4.4.4","v4.4.5","v4.4.6","v4.4.7","v4.5.0","v4.5.1","v4.6.0","v4.7.0","v4.7.1","v4.7.2","v4.7.3","v4.8.0","v4.8.1","v4.8.2","v4.9.0","v4.9.1","v4.9.2","v4.9.3","v4.9.4","v4.9.5","v5.0.0","v5.1.0","v5.1.1","v5.10.0","v5.11.0","v5.12.0","v5.13.0","v5.14.0","v5.15.0","v5.15.1","v5.15.2","v5.16.0","v5.17.0","v5.17.1","v5.18.0","v5.19.0","v5.19.1","v5.2.0","v5.20.0","v5.21.0","v5.21.1","v5.21.2","v5.22.0","v5.22.1","v5.23.0","v5.23.4","v5.24.0","v5.25.0","v5.25.1","v5.25.2","v5.25.3","v5.26.0","v5.26.1","v5.26.2","v5.26.3","v5.26.4","v5.26.5","v5.27.0","v5.27.1","v5.27.2","v5.28.0","v5.28.1","v5.28.2","v5.3.0","v5.4.0","v5.5.0","v5.5.1","v5.6.0","v5.6.1","v5.7.0","v5.8.0","v5.8.1","v5.8.2","v5.9.1","v6.0.0","v6.0.1","v6.1.0","v6.10.0","v6.10.1","v6.10.2","v6.11.0","v6.11.1","v6.12.0","v6.13.0","v6.14.0","v6.14.1","v6.15.0","v6.16.0","v6.16.1","v6.17.0","v6.18.0","v6.18.1","v6.18.2","v6.19.0","v6.19.1","v6.19.2","v6.19.3","v6.19.4","v6.19.5","v6.19.6","v6.19.7","v6.19.8","v6.2.0","v6.2.1","v6.20.0","v6.20.1","v6.21.0","v6.21.1","v6.21.2","v6.21.3","v6.22.0","v6.23.0","v6.3.0","v6.4.0","v6.5.0","v6.6.0","v6.6.1","v6.6.2","v6.7.0","v6.7.1","v6.8.0","v6.9.0","v7.0.0","v7.1.0","v7.1.1","v7.10.0","v7.11.0","v7.12.0","v7.13.0","v7.14.0","v7.15.0","v7.16.0","v7.17.0","v7.18.0","v7.18.1","v7.18.2","v7.19.0","v7.19.1","v7.19.2","v7.2.0","v7.2.1","v7.2.2","v7.2.3","v7.20.0","v7.21.0","v7.22.0","v7.23.0","v7.3.0","v7.4.0","v7.5.0","v7.6.0","v7.7.0","v7.8.0","v7.9.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-1527.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N"}]}