A crafted JavaScript input can trigger an internal assertion failure in QuickJS release 2025-09-13, fixed in commit 1dbba8a88eaa40d15a8a9b70bb1a0b8fb5b552e6 (2025-12-11), in file gc_decref_child in quickjs.c, when executed with the qjs interpreter using the -m option. This leads to an abort (SIGABRT) during garbage collection and causes a denial-of-service.