Memory corruption via re-entrant object printing

Use-after-free in QuickJS 2025-04-26 allows attackers to corrupt memory by printing attacker-controlled arrays, maps, or sets. js_print_object caches an array length or walks map and set records, while js_print_value can invoke a callback that resizes the array or removes a current record before iteration resumes. Exploitation requires attacker-controlled JavaScript to trigger re-entrant mutation during value printing; the resulting stale access can corrupt memory or crash the host process.