Medium severity · published Mar 13, 2026
CVE-2026-24097
Authenticated Host Enumeration via Observable Response Discrepancy on Agent Register Existing Endpoint
4.3
CVSS
0.2%
EPSS
No
On KEV
Description
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/register_existing endpoint, which could lead to information disclosure.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 16% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CH
Checkmk · Checkmk GmbH
2.4.0 before 2.4.0p23; 2.3.0 before 2.3.0p43; 2.2.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-24097
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-24097
Vendor Advisory
https://checkmk.com/werk/18993
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