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CVE-2026-1527

undici is vulnerable to CRLF Injection via upgrade option PUBLISHED

Description (CNA)

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 (CNA)

Vendor / productVersions
undici / undiciaffected < 6.24.0; 7.0.0 < 7.24.0; unaffected 6.24.0: 7.24.0

CWE

CWE-93

References

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.