Report: CVE-2026-2229 - undici is vulnerable to Unhandled Exception in undici WebSocket Client Due to Inv...

Report: CVE-2026-2229 - undici is vulnerable to Unhandled Exception in undici WebSocket Client Due to Inv...

CVE ID :CVE-2026-2229 Published : March 12, 2026, 9:16 p.m. | 49 minutes ago Description :ImpactThe undici WebSocket client is vulnerable to a denial-of-service attack due to improper validation of the server_max_window_bits parameter in the permessage-deflate extension. When a WebSocket client connects to a server, it automatically advertises support for permessage-deflate compression. A malicious server can respond with an out-of-range server_max_window_bits value (outside zlib's valid range of 8-15). When the server subsequently sends a compressed frame, the client attempts to create a zlib InflateRaw instance with the invalid windowBits value, causing a synchronous RangeError exception that is not caught, resulting in immediate process termination. The vulnerability exists because: * The isValidClientWindowBits() function only validates that the value contains ASCII digits, not that it falls within the valid range 8-15 * The createInflateRaw() call is not wrapped in a try-catch block * The resulting exception propagates up through the call stack and crashes the Node.js process Severity: 7.5 | HIGH Visit the link for more details, such as CVSS details, affected products, timeline, and more...

CVE Details

Severity
HIGH
Published
March 12, 2026
Affected Product: Node.js