CVE-2026-1527: fallo de gravedad media en undici
undici is vulnerable to CRLF Injection via upgrade option
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
13Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 4.6epss 0.3%
ImpactWhen an application passes user-controlled input to the upgrade option of client.request(), an attacker can inject CRLF sequences (\r\n) to:
* Inject arbitrary HTTP headers
* Terminate the HTTP request prematurely and smuggle raw data to non-HTTP services (Redis, Memcached, Elasticsearch)
The vulnerability exists because undici writes the upgrade value directly to the socket without validating for invalid header characters:
// lib/dispatcher/client-h1.js:1121
if (upgrade) {
header += `connection: upgrade\r\nupgrade: ${upgrade}\r\n`
}
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
Productos afectados
undici · undiciCVEs relacionadas — undici
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