Description
h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit edd7a120bfc4af11ac0cbebce2a43cc1f93f9af1, when h2o processes a QPACK instruction sent from the peer over HTTP/3, lib/http3/qpack.c might allocate an on-stack buffer as large as approximately 800 KB by calling alloca, which exceeds the default pthread stack size used by musl libc and causes the h2o server to crash with a segmentation fault while touching the guard page. This issue is fixed in commit edd7a120bfc4af11ac0cbebce2a43cc1f93f9af1.
Problem types
CWE-789: Memory Allocation with Excessive Size Value
Product status
References
github.com/h2o/h2o/security/advisories/GHSA-432c-8xmj-frmq
github.com/...ommit/edd7a120bfc4af11ac0cbebce2a43cc1f93f9af1