Curated security research, vulnerabilities, advisories and tools for practitioners.

PHP 8.5.5: var_destroy __destruct Reentrancy Heap UAF and Exploitation

github.com | vulnerability | High | #rce | #php | #exploitation | #poc | #reentrancy | #uaf

Summary

# PHP 8.5.5 — `var_destroy` `__destruct` reentrancy UAF > Sister bug to Calif.io's MAD Bugs PHP unserialize finding (2026-05-01). Independent root cause; survives the fix Calif proposes for...

Why it matters

Demonstrates how subtle lock-free destructor reentry in complex serialization state machines can yield reliable memory corruption and RCE, even when explicit magic method dispatches are guarded.
Vendor
PHP
Product
PHP
Affected versions
PHP 8.5.5 (likely 7.x - 8.5.x)
Published
Collected