CVE-2026-24097: Authenticated Host Enumeration via Observable Response Discrepancy on Agent Register Existing Endpoint

Published Mar 13, 2026
·
Updated

Improper permission enforcement in Checkmk versions 2.4.0 before 2.4.0p23, 2.3.0 before 2.3.0p43, and 2.2.0 (EOL) allows authenticated users to enumerate existing hosts by observing different HTTP response codes in agent-receiver/registerexisting endpoint, which could lead to information disclosure.

Affected Software

138 affected components
Tribe29 Checkmk<2.4.0p23
Tribe29 Checkmk<2.3.0p43
Tribe29 Checkmk
Checkmk Checkmk=2.2.0
Checkmk Checkmk=2.2.0-b1
Checkmk Checkmk=2.2.0-b2
Checkmk Checkmk=2.2.0-b3
Checkmk Checkmk=2.2.0-b4
Checkmk Checkmk=2.2.0-b5
Checkmk Checkmk=2.2.0-b6
Checkmk Checkmk=2.2.0-b7
Checkmk Checkmk=2.2.0-b8
Checkmk Checkmk=2.2.0-i1
Checkmk Checkmk=2.2.0-p1
Checkmk Checkmk=2.2.0-p10
Checkmk Checkmk=2.2.0-p11
Checkmk Checkmk=2.2.0-p12
Checkmk Checkmk=2.2.0-p13
Checkmk Checkmk=2.2.0-p14
Checkmk Checkmk=2.2.0-p15
Checkmk Checkmk=2.2.0-p16
Checkmk Checkmk=2.2.0-p17
Checkmk Checkmk=2.2.0-p18
Checkmk Checkmk=2.2.0-p19
Checkmk Checkmk=2.2.0-p2
Checkmk Checkmk=2.2.0-p20
Checkmk Checkmk=2.2.0-p21
Checkmk Checkmk=2.2.0-p22
Checkmk Checkmk=2.2.0-p23
Checkmk Checkmk=2.2.0-p24
Checkmk Checkmk=2.2.0-p25
Checkmk Checkmk=2.2.0-p26
Checkmk Checkmk=2.2.0-p27
Checkmk Checkmk=2.2.0-p28
Checkmk Checkmk=2.2.0-p29
Checkmk Checkmk=2.2.0-p3
Checkmk Checkmk=2.2.0-p30
Checkmk Checkmk=2.2.0-p31
Checkmk Checkmk=2.2.0-p32
Checkmk Checkmk=2.2.0-p33
Checkmk Checkmk=2.2.0-p34
Checkmk Checkmk=2.2.0-p35
Checkmk Checkmk=2.2.0-p36
Checkmk Checkmk=2.2.0-p37
Checkmk Checkmk=2.2.0-p38
Checkmk Checkmk=2.2.0-p39
Checkmk Checkmk=2.2.0-p4
Checkmk Checkmk=2.2.0-p40
Checkmk Checkmk=2.2.0-p41
Checkmk Checkmk=2.2.0-p42
Checkmk Checkmk=2.2.0-p43
Checkmk Checkmk=2.2.0-p44
Checkmk Checkmk=2.2.0-p45
Checkmk Checkmk=2.2.0-p46
Checkmk Checkmk=2.2.0-p47
Checkmk Checkmk=2.2.0-p5
Checkmk Checkmk=2.2.0-p6
Checkmk Checkmk=2.2.0-p7
Checkmk Checkmk=2.2.0-p8
Checkmk Checkmk=2.2.0-p9
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-p42
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-p19
Checkmk Checkmk=2.4.0-p2
Checkmk Checkmk=2.4.0-p20
Checkmk Checkmk=2.4.0-p21
Checkmk Checkmk=2.4.0-p22
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

Mar 13, 2026
CVE Published
via MITRE·09:40 AM
Data Sourced
via MITRE·09:40 AM
DescriptionWeakness
Data Sourced
via NVD·07:54 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2026-24097?

CVE-2026-24097 is considered a medium severity vulnerability due to improper permission enforcement that allows authenticated users to enumerate existing hosts.

2

How do I fix CVE-2026-24097?

To fix CVE-2026-24097, upgrade Checkmk to version 2.4.0p23 or 2.3.0p43 or later.

3

What versions of Checkmk are affected by CVE-2026-24097?

CVE-2026-24097 affects Checkmk versions 2.4.0 before 2.4.0p23, 2.3.0 before 2.3.0p43, and all versions of 2.2.0.

4

What type of vulnerability is CVE-2026-24097?

CVE-2026-24097 is an authenticated host enumeration vulnerability that results from observable response discrepancies.

5

Who is impacted by CVE-2026-24097?

Authentic users of Checkmk versions 2.4.0 before 2.4.0p23, 2.3.0 before 2.3.0p43, and 2.2.0 are impacted by CVE-2026-24097.

Company

Resources

Contact

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info@secalerts.co
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