CVE-2026-61550
CriticalCVSS 9.8Summary
Icinga 2 from 2.8 to 2.14.9, 2.15.4, and 2.16.2 has a vulnerability in certificate update JSON-RPC message handling where the sender is not validated as a trusted endpoint. An unauthenticated attacker with access to TCP port 5665 can replace the node certificate and CA certificate, impersonate a trusted node, and take control.
Risk Assessment
An attacker can take control of a monitoring node, potentially leading to compromise of monitoring data integrity and further attacks in the infrastructure.
Recommendation
Upgrade Icinga 2 to version 2.14.9, 2.15.4, or 2.16.2. Restrict access to port 5665 to trusted clients only.
Other vulnerabilities in Icinga 2
See all- CVE-2026-61552High
Icinga 2 from 2.4 until 2.14.9, 2.15.4, and 2.16.2 writes attacker-controlled template names into generated configuration without escaping them. An authenticated ApiUser with an objects/create/* permission can inject Icinga 2 DSL configuration, create additional objects, and exceed the user's assigned privileges.
- CVE-2026-61551High
Icinga 2 prior to 2.14.9, 2.15.4, and 2.16.2 does not bound JSON nesting depth, allowing deeply nested JSON to exhaust the call stack. The affected JSON parsing paths are reachable by unauthenticated network clients through the Icinga 2 service on TCP port 5665, allowing a remote attacker to crash the process.
Original NVD description (English source)
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.