CVE-2026-1527 (GCVE-0-2026-1527)

Vulnerability from cvelistv5 – Published: 2026-03-12 20:17 – Updated: 2026-03-13 18:06
VLAI
Title
undici is vulnerable to CRLF Injection via upgrade option
Summary
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` }
Severity
4.6 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
CWE
  • CWE-93 - Improper neutralization of CRLF sequences ('CRLF injection')
Assigner
References
Impacted products
Vendor Product Version
undici undici Affected: < 6.24.0; 7.0.0 < 7.24.0
Unaffected: 6.24.0: 7.24.0
Create a notification for this product.
Credits
Matteo Collina Ulises Gascón Raul Vega del Valle
Show details on NVD website
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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