Software component issue could make the service unavailable
undici is an HTTP client library for Node.js. In versions 8.11.0 and 8.11.1, its experimental WebSocket client, which is enabled by default when HTTP/2 is allowed, mishandles a failed WebSocket handshake over HTTP/2: the…
What happened
- undici is an HTTP client library for Node.js. In versions 8.11.0 and 8.11.1, its experimental WebSocket client, which is enabled by default when HTTP/2 is allowed, mishandles a failed WebSocket handshake over HTTP/2: the request is already marked completed, so the abort becomes a no-op and the underlying HTTP/2 stream is left open with no error listener. When a malicious server then destroys the connection, the orphaned stream emits an unhandled error and the Node.js process exits. A remote, unauthenticated server can therefore crash any client that opens a WebSocket to it over HTTP/2, resulting in a denial of service. The issue is fixed in undici 8.11.2, and users should upgrade to 8.11.2 or later. As a workaround, set allowH2 to false to disable HTTP/2 for WebSocket connections, or avoid opening WebSocket connections to untrusted servers.Security Advisory CVE-2026-109855
- undici is an HTTP client library for Node.js. In versions 8.11.0 and 8.11.1, its experimental WebSocket client, which is enabled by default when HTTP/2 is allowed, mishandles a failed WebSocket handshake over HTTP/2: the request is already marked completed, so the abort becomes a no-op and the underlying HTTP/2 stream…Advisory description (CVE-2026-109855)
Contributing factors stated by the source
- undici is an HTTP client library for Node.js. In versions 8.11.0 and 8.11.1, its experimental WebSocket client, which is enabled by default when HTTP/2 is allowed, mishandles a failed WebSocket handshake over HTTP/2: the request is already marked completed, so the abort becomes a no-op and the underlying HTTP/2 stream…
The failure pattern
Watch the pattern: Retry amplification and runaway resource consumption
Related standards
CollectSEA's mapping through this incident's failure pattern; not an official determination by the standards bodies.
Building something similar?
Describe your design and see every precedent that applies, with safeguards you can hand to your coding agent.
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Design reference: AWS guidance on timeouts, retries and backoff with jitter
AWS describes retries as powerful but dangerous: when a dependency is struggling, too many retries can amplify load and turn a partial failure into a retry storm.
Software component issue could make the service unavailable
A public security advisory describes this issue. Review the linked source for the technical details and remediation guidance.
Software component issue could make the service unavailable
A public security advisory describes this issue. Review the linked source for the technical details and remediation guidance.
Software component issue could make the service unavailable
pupnp is an SDK for development of UPnP device and control point applications. Prior to 2.0.2, rawtoint in upnp/src/genlib/net/http/httpparser.c parses Content-Length with strtol and casts the resulting long to a 32-bit…