CVE-2026-2859
Medium
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 unauthenticated users to enumerate existing hosts by observing different HTTP response codes in deploy_agent endpoint, which could lead to information disclosure.
SeverityMedium
CVSS4.3
Exploit probability—
ProductCheckmk
PublishedMar 13, 2026
First seenMar 13, 2026
Weakness typeCWE-204CWE-204
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| checkmk checkmk | 2.2.0, 2.3.0, 2.4.0 | — |
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