CVE-2025-65000: Exposure of SSH Private Keys in Remote Alert Handlers (Linux) Rule

Published Dec 18, 2025
·
Updated

SSH private keys of the "Remote alert handlers (Linux)" rule were exposed in the rule page's HTML source in Checkmk <= 2.4.0p18 and all versions of Checkmk 2.3.0. This potentially allowed unauthorized triggering of predefined alert handlers on hosts where the handler was deployed.

Affected Software

75 affected components
Checkmk Checkmk<=2.4.0p18
Checkmk Checkmk=2.2.0
Checkmk Checkmk=2.3.0
Checkmk Checkmk=2.3.0-b1
Checkmk Checkmk=2.3.0-b2
Checkmk Checkmk=2.3.0-b3
Checkmk Checkmk=2.3.0-b4
Checkmk Checkmk=2.3.0-b5
Checkmk Checkmk=2.3.0-b6
Checkmk Checkmk=2.3.0-p1
Checkmk Checkmk=2.3.0-p10
Checkmk Checkmk=2.3.0-p11
Checkmk Checkmk=2.3.0-p12
Checkmk Checkmk=2.3.0-p13
Checkmk Checkmk=2.3.0-p14
Checkmk Checkmk=2.3.0-p15
Checkmk Checkmk=2.3.0-p16
Checkmk Checkmk=2.3.0-p17
Checkmk Checkmk=2.3.0-p18
Checkmk Checkmk=2.3.0-p19
Checkmk Checkmk=2.3.0-p2
Checkmk Checkmk=2.3.0-p20
Checkmk Checkmk=2.3.0-p21
Checkmk Checkmk=2.3.0-p22
Checkmk Checkmk=2.3.0-p23
Checkmk Checkmk=2.3.0-p24
Checkmk Checkmk=2.3.0-p25
Checkmk Checkmk=2.3.0-p26
Checkmk Checkmk=2.3.0-p27
Checkmk Checkmk=2.3.0-p28
Checkmk Checkmk=2.3.0-p29
Checkmk Checkmk=2.3.0-p3
Checkmk Checkmk=2.3.0-p30
Checkmk Checkmk=2.3.0-p31
Checkmk Checkmk=2.3.0-p32
Checkmk Checkmk=2.3.0-p33
Checkmk Checkmk=2.3.0-p34
Checkmk Checkmk=2.3.0-p35
Checkmk Checkmk=2.3.0-p36
Checkmk Checkmk=2.3.0-p37
Checkmk Checkmk=2.3.0-p38
Checkmk Checkmk=2.3.0-p39
Checkmk Checkmk=2.3.0-p4
Checkmk Checkmk=2.3.0-p40
Checkmk Checkmk=2.3.0-p41
Checkmk Checkmk=2.3.0-p5
Checkmk Checkmk=2.3.0-p6
Checkmk Checkmk=2.3.0-p7
Checkmk Checkmk=2.3.0-p8
Checkmk Checkmk=2.3.0-p9
Checkmk Checkmk=2.4.0
Checkmk Checkmk=2.4.0-b1
Checkmk Checkmk=2.4.0-b2
Checkmk Checkmk=2.4.0-b3
Checkmk Checkmk=2.4.0-b4
Checkmk Checkmk=2.4.0-b5
Checkmk Checkmk=2.4.0-b6
Checkmk Checkmk=2.4.0-p1
Checkmk Checkmk=2.4.0-p10
Checkmk Checkmk=2.4.0-p11
Checkmk Checkmk=2.4.0-p12
Checkmk Checkmk=2.4.0-p13
Checkmk Checkmk=2.4.0-p14
Checkmk Checkmk=2.4.0-p15
Checkmk Checkmk=2.4.0-p16
Checkmk Checkmk=2.4.0-p17
Checkmk Checkmk=2.4.0-p18
Checkmk Checkmk=2.4.0-p2
Checkmk Checkmk=2.4.0-p3
Checkmk Checkmk=2.4.0-p4
Checkmk Checkmk=2.4.0-p5
Checkmk Checkmk=2.4.0-p6
Checkmk Checkmk=2.4.0-p7
Checkmk Checkmk=2.4.0-p8
Checkmk Checkmk=2.4.0-p9

Event History

Dec 18, 2025
CVE Published
via MITRE·02:04 PM
Data Sourced
via MITRE·02:04 PM
DescriptionWeakness
Data Sourced
via NVD·02:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2025-65000?

CVE-2025-65000 has a high severity rating due to the exposure of SSH private keys.

2

How do I fix CVE-2025-65000?

To fix CVE-2025-65000, upgrade to Checkmk version 2.4.0p19 or later.

3

What are the risks associated with CVE-2025-65000?

The risks include unauthorized access to the system via exposed SSH private keys, allowing for potential malicious activity.

4

Which versions of Checkmk are affected by CVE-2025-65000?

CVE-2025-65000 affects Checkmk versions up to and including 2.4.0p18 and all versions of Checkmk 2.3.0.

5

What should I do if I can't immediately upgrade to fix CVE-2025-65000?

If an immediate upgrade isn't possible, review and secure your rule page to prevent access to the HTML source.

Contact

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