CVE-2026-66583 WordPress Forminator plugin <= 1.57.0 - PHP Object Injection vulnerability
Unauthenticated attackers can exploit PHP object injection in the Forminator plugin to potentially execute arbitrary code.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-66583?
CVE-2026-66583 is a critical unsafe deserialization vulnerability in WPMU DEV Forminator, published on 20 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Unauthenticated PHP Object Injection in Forminator <= 1.57.0 versions.
Weakness: CWE-502
Which versions are affected by CVE-2026-66583?
How do I fix CVE-2026-66583?
No fix has been published for CVE-2026-66583 yet. Limit exposure of the affected software until one is available.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-66583 being exploited?
There is no known exploitation of CVE-2026-66583 in the wild and no public exploit code.
Sources
Also known as GHSA-f837-mqhp-xxmg.