Node.js · Report #3531737
Memory leak in Node.js HTTP/2 server via WINDOW_UPDATE on stream 0 leads to resource exhaustion
Validstatus
mediumseverity
7upvotes
30 Mar 2026disclosed
Summary
A memory leak occurs in Node.js HTTP/2 servers when a client sends WINDOW_UPDATE frames on stream 0 (connection-level) that cause the flow control window to exceed the maximum value of 2³¹-1. The server correctly sends a GOAWAY frame, but the Http2Session object is never cleaned up.
This vulnerability affects HTTP2 users on Node.js 20, 22, 24 and 25.
How it was found
The write-up for this report has not been downloaded yet, or the program disclosed it without one. Read it on HackerOne.