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CVE PROGRAM SOURCE RECORD4.6 Medium

CVE-2026-1527

undici is vulnerable to CRLF Injection via upgrade option

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Status
Published
Published
Updated
Assigning organization
openjs

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` }

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

undici undici

Default version status: unaffected

  • < 6.24.0; 7.0.0 < 7.24.0affected
  • 6.24.0: 7.24.0unaffected

References