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` }
CVSS Metrics
- Vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
- Attack Vector
- network
- Complexity
- low
- Privileges
- low
- User Action
- required
- Scope
- unchanged
- Confidentiality
- low
- Integrity
- low
- Availability
- none
- Weaknesses
- CWE-93
Metadata
- Primary Vendor
- UNKNOWN
- Published
- 3/12/2026
- Last Modified
- 3/12/2026
- Source
- NIST NVD
- Note: Verify all details with official vendor sources before applying patches.
Affected Products
No affected products information available.
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