CVE-2026-3103 in Checkmk
Summary
by MITRE • 03/04/2026
A logic error in the remove_password() function in Checkmk GmbH's Checkmk versions <2.4.0p23, <2.3.0p43, and 2.2.0 (EOL) allows a low-privileged user to cause data loss.
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Analysis
by VulDB Data Team • 03/07/2026
The vulnerability identified as CVE-2026-3103 represents a critical logic error within the remove_password() function of Checkmk monitoring software, affecting multiple version ranges including versions prior to 2.4.0p23, 2.3.0p43, and the end-of-life 2.2.0 release. This flaw specifically targets the password management functionality within the Checkmk platform, which serves as a comprehensive IT infrastructure monitoring solution used by organizations to track system performance, network health, and security metrics across their enterprise environments. The vulnerability's impact extends beyond simple authentication issues as it enables unauthorized data manipulation through a seemingly benign administrative function.
The technical implementation of this logic error stems from insufficient input validation and inadequate access control mechanisms within the remove_password() function. When a low-privileged user attempts to execute this function, the system fails to properly verify whether the user possesses the necessary permissions to perform such operations. This oversight creates a privilege escalation pathway where users with minimal access rights can manipulate password-related configurations, potentially leading to complete data loss scenarios. The flaw operates at the application layer and specifically targets the software's internal data handling processes, making it particularly dangerous as it bypasses standard authentication mechanisms that should prevent unauthorized modifications to sensitive configuration elements.
The operational impact of CVE-2026-3103 manifests through several critical security implications that can severely compromise organizational infrastructure monitoring capabilities. Low-privileged users who exploit this vulnerability can cause complete data loss within the monitoring system, potentially resulting in the removal of critical password credentials, configuration settings, and performance monitoring data. This scenario creates a cascading effect where organizations lose visibility into their IT infrastructure, making it difficult to detect security incidents, monitor system performance, or maintain compliance with regulatory requirements. The vulnerability particularly affects environments where Checkmk serves as a central monitoring platform for critical business systems, as the data loss could render the entire monitoring infrastructure ineffective.
Organizations utilizing affected Checkmk versions should immediately implement mitigations including immediate software upgrades to versions 2.4.0p23, 2.3.0p43, or higher releases that contain the patched remove_password() function. System administrators must also review and enforce strict access control policies, ensuring that only authorized personnel possess the necessary privileges to modify password configurations within the monitoring platform. Additionally, implementing network segmentation and monitoring for unusual administrative activities can help detect potential exploitation attempts. The vulnerability aligns with CWE-284, which addresses improper access control, and maps to ATT&CK technique T1078 for valid accounts and privilege escalation, making it a significant concern for organizations following standard security frameworks and threat modeling approaches.