Critical severity · published Sep 18, 2026
CVE-2026-61550
Icinga 2: Improper access control for JSON-RPC update certificate messages
9.8
CVSS
0.7%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 52% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
IC
icinga2 · Icinga
>= 2.8, < 2.14.9; >= 2.15.0, < 2.15.4; >= 2.16.0, < 2.16.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-61550
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-61550
github.com
https://github.com/Icinga/icinga2/commit/4b7fb3405f4616a24b2b55e20f603a56b7dd6ad0
github.com
https://github.com/Icinga/icinga2/commit/6c2e0db3819f859910a4ae265461cb51b1d2039c
github.com
https://github.com/Icinga/icinga2/commit/a6f7cc7a4ef8beed023b24416106822d6940c4c0
github.com
https://github.com/Icinga/icinga2/commit/d37b0cfd7d9595ae2f02fadb3d724c98d8620f81
github.com
https://github.com/Icinga/icinga2/pull/10907
github.com
https://github.com/Icinga/icinga2/releases/tag/v2.14.9
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