CVE-2026-61550 Icinga 2: Improper access control for JSON-RPC update certificate messages
Unauthenticated attackers can replace node certificates via JSON-RPC, impersonate trusted nodes, and take control of the monitoring system.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-61550?
CVE-2026-61550 is a critical missing authorization vulnerability in icinga2, published on 18 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Icinga 2 is an open source monitoring system. From 2.8 until 2.14.9, 2.15.4, and 2.16.2, certificate update JSON-RPC message handling does not validate that the sender is a trusted endpoint. An unauthenticated network attacker able to connect to TCP port 5665 can replace the node certificate and trusted CA certificate, impersonate a trusted node, and take control of the node. This issue is fixed in versions 2.14.9, 2.15.4, and 2.16.2.
Weakness: CWE-862
Which versions are affected by CVE-2026-61550?
How do I fix CVE-2026-61550?
Upgrade to a fixed version.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-61550 being exploited?
There is no known exploitation of CVE-2026-61550 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-61550, GHSA-vj39-ww8j-vvx5, UBUNTU-CVE-2026-61550.