That post appears to show the same stack trace as this reported issue https://github.com/php/php-src/issues/24488, which is a confirmed GC regression in 8.5.12 but it is not exploitable (the allocator's shadow protection kills it), and it does not result in RCE and is not a critical CVE.

It's a very different shape to the other two CVEs, and a use-after-free doesn't necessarily immediately imply a critical CVE.