CVE-2026-80197 kimai CVE debrief

Who should care

Users of Kimai versions before 2.57.0, administrators of Kimai installations, security teams monitoring for potential cross-user tampering vulnerabilities, and operators who manage or interact with timesheet data should be aware of this vulnerability. They should verify user access controls, limit user permissions, and monitor for suspicious activity to prevent exploitation. Additionally, they should review and adjust business logic for timesheet management to prevent similar vulnerabilities in the future. Security teams should also consider implementing compensating controls for exposed systems while remediation is scheduled and verified. Asset inventory management and source tracking can help identify and prioritize affected systems for remediation. Rollback/change windows can help manage the deployment of patches or mitigations. Monitoring and detection capabilities can help identify potential exploitation attempts. Vulnerability management processes should be updated to include this vulnerability and prioritize its remediation based on the severity of the vulnerability and the potential impact on the organization. Reviewing and adjusting incident response plans to include procedures for responding to potential exploitation of this vulnerability is also recommended. Finally, verifying that patches or mitigations have been successfully deployed and that systems are no longer vulnerable is crucial to preventing exploitation. This may involve retesting remediated assets and closing the item only after evidence is documented. CVE Program and NVD provide additional details on this vulnerability, which can inform these efforts. To ensure comprehensive protection, consider implementing a defense-in-depth strategy that includes multiple layers of security controls and mitigation measures. This can help reduce the risk of exploitation and minimize potential impact in the event of a successful attack. By taking a proactive and multi-faceted approach to security, organizations can better protect themselves against this and other vulnerabilities. To further enhance security, consider implementing a continuous monitoring program to identify and address potential security

Technical summary

CVE-2026-80197 is an improper authorization vulnerability in Kimai before 2.57.0. Authenticated users can manipulate other users' favorite timesheets by referencing their timesheet identifier, enabling cross-user business-state tampering without administrative privileges. This vulnerability allows attackers to add or remove timesheet entries from another user's favorite list, potentially leading to unauthorized changes in business state.

Defensive priority

Authenticated users may be able to manipulate other users' favorite timesheets; verify and limit user access.

Recommended defensive actions

• Verify user access controls for favorite timesheet management
• Limit user permissions to prevent cross-user tampering
• Monitor for suspicious activity on timesheet favorites
• Update Kimai to version 2.57.0 or later
• Review and adjust business logic for timesheet management

Evidence notes

The CVE-2026-80197 record indicates an improper authorization vulnerability in Kimai before 2.57.0, allowing authenticated users to add or remove timesheet entries from another user's favorite list. Official records from the CVE Program and NVD provide details. To verify and mitigate this vulnerability, defenders should review user access controls, limit user permissions, monitor for suspicious activity, and update Kimai to version 2.57.0 or later. Additionally, they should assess their current user access management and timesheet configurations to ensure they are not exposed to cross-user tampering.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.