CVE-2026-1527

Publication date 12 March 2026

Last updated 18 March 2026


Ubuntu priority

Cvss 3 Severity Score

4.6 · Medium

Score breakdown

Description

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` }

Status

Package Ubuntu Release Status
node-undici 25.10 questing
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy Not in release

Severity score breakdown

Parameter Value
Base score 4.6 · Medium
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction Required
Scope Unchanged
Confidentiality Low
Integrity impact Low
Availability impact None
Vector CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

Access our resources on patching vulnerabilities