CVE-2026-59783 Server DoS via binary items
Attackers can crash Zabbix Server or Proxy by sending NULL bytes in binary items, causing denial of service in MySQL/MariaDB deployments.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-59783?
CVE-2026-59783 is a low-severity denial of service vulnerability in Zabbix, published on 5 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
The Zabbix Server/Proxy has a vulnerability where binary items can crash the Server/Proxy on certain NULL byte input leading to potential loss of availability. This only affects deployments where MySQL/MariaDB database is used as the Zabbix database.
Weakness: CWE-787
Which versions are affected by CVE-2026-59783?
How do I fix CVE-2026-59783?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-59783 being exploited?
There is no known exploitation of CVE-2026-59783 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-59783, GHSA-2835-94vr-22j6, UBUNTU-CVE-2026-59783.