Exposure of session signing secret in Checkmk <2.4.0p23, <2.3.0p45 and 2.2.0 allows an administrator of a remote site with config sync enabled to hijack sessions on the central site by forging session cookies.

Attack Vector Network

Attack Complexity Low

Privileges Required High

Attack Requirements Present

User Interaction Passive

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00036.

Exploitation none

Automatable no

Technical Impact total

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
Checkmk GmbH Checkmk unaffected
Version Status Constraints
2.4.0 affected < 2.4.0p23
2.3.0 affected < 2.3.0p45
2.2.0 affected —

No data.

No data.

No data.

Project Subscriptions

Vendors Products
Checkmk Subscribe
Checkmk Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://checkmk.com/werk/18954 cve-icon cve-icon
History

Tue, 24 Mar 2026 14:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Tue, 24 Mar 2026 11:45:00 +0000

Type Values Removed Values Added
Description Exposure of session signing secret in Checkmk <2.4.0p23, <2.3.0p45 and 2.2.0 allows an administrator of a remote site with config sync enabled to hijack sessions on the central site by forging session cookies.
Title Session hijacking via exposed session signing secret in distributed Checkmk setups
First Time appeared Checkmk
Checkmk checkmk
Weaknesses CWE-522
CPEs cpe:2.3:a:checkmk:checkmk:*:*:*:*:*:*:*:*
Vendors & Products Checkmk
Checkmk checkmk
References
Metrics cvssV4_0

{'score': 7.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: Checkmk

Published:

Updated: 2026-03-24T14:06:08.395Z

Reserved: 2025-11-12T09:16:24.093Z

Link: CVE-2025-64998

cve-icon Vulnrichment

Updated: 2026-03-24T14:05:15.260Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-03-24T12:16:11.930

Modified: 2026-03-24T15:53:48.067

Link: CVE-2025-64998

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses