CVE-2024-11235

Date: April 4, 2025

In PHP prior to 8.3.19 and 8.4.5, the exception handler frees variables via cleanup_live_vars for termination. However, the subsequent php_request_shutdown performs reference counting on these variables using zend_gc_refcount(read) and zend_gc_delref(write), resulting in use-after-free. Since zend_mm_free_small stores metadata in freed memory chunks, this use-after-free vulnerability may allows manipulation of the Zend allocator through reference count behaviors.