SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityReceived

CVE-2026-61550

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.

CRITICAL 9.8EPSS 0.37%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.37%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.37% probability · 31th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-862
Source
security-advisories@github.com
EPSS trend
0%3%5%19 September 2026: 0.37%19 September 202619 September 2026

EPSS 0.4% since 19 September 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.