Checkmk up to 2.2.0/2.3.0p44/2.4.0p22 Session Cookie insufficiently protected credentials

CVSS Meta Temp Score
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CTI Interest Score
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4.5$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Checkmk up to 2.2.0/2.3.0p44/2.4.0p22. This affects an unknown part of the component Session Cookie Handler. This manipulation causes insufficiently protected credentials. This vulnerability is tracked as CVE-2025-64998. The attack is possible to be carried out remotely. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Checkmk up to 2.2.0/2.3.0p44/2.4.0p22. It has been declared as problematic. Affected by this vulnerability is an unknown functionality of the component Session Cookie Handler. The manipulation with an unknown input leads to a insufficiently protected credentials vulnerability. The CWE definition for the vulnerability is CWE-522. The product transmits or stores authentication credentials, but it uses an insecure method that is susceptible to unauthorized interception and/or retrieval. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at checkmk.com. This vulnerability is known as CVE-2025-64998 since 11/12/2025. The exploitation appears to be easy. The attack can be launched remotely. Additional levels of successful authentication are required for exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1552 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 304142 (Linux Distros Unpatched Vulnerability : CVE-2025-64998), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.3.0p45 or 2.4.0p23 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (304142). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.7
VulDB Meta Temp Score: 4.5

VulDB Base Score: 4.7
VulDB Temp Score: 4.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Insufficiently protected credentials
CWE: CWE-522
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 304142
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-64998

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Checkmk 2.3.0p45/2.4.0p23

Timelineinfo

11/12/2025 CVE reserved
03/24/2026 +132 days Advisory disclosed
03/24/2026 +0 days VulDB entry created
03/29/2026 +5 days VulDB entry last update

Sourcesinfo

Advisory: checkmk.com
Status: Confirmed

CVE: CVE-2025-64998 (🔒)
GCVE (CVE): GCVE-0-2025-64998
GCVE (VulDB): GCVE-100-352717

Entryinfo

Created: 03/24/2026 13:56
Updated: 03/29/2026 01:48
Changes: 03/24/2026 13:56 (65), 03/28/2026 14:35 (2), 03/29/2026 01:48 (1)
Complete: 🔍
Cache ID: 216:072:103

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