CVE-2026-23923 Unauthenticated arbitrary PHP class instantiation
Unauthenticated attackers can instantiate arbitrary PHP classes via the Frontend validate action, potentially leading to code execution depending on the environment.
- 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-2026-23923?
CVE-2026-23923 is a medium-severity code injection vulnerability in Zabbix Zabbix, published on 24 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An unauthenticated attacker can exploit the Frontend 'validate' action to blindly instantiate arbitrary PHP classes. The impact depends on environment setup but appears limited at this time.
Weakness: CWE-470
Which versions are affected by CVE-2026-23923?
It affects 1 product.
Products include Zabbix Zabbix.
How do I fix CVE-2026-23923?
No fix has been published for CVE-2026-23923 yet. Limit exposure of the affected software until one is available.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-23923 being exploited?
There is no known exploitation of CVE-2026-23923 in the wild and no public exploit code.
Other vulnerabilities in Zabbix Zabbix
Sources
Also known as GHSA-4mp5-p9jh-3rv5.