CVE-2026-31881 in Runtipi
Summary
by MITRE • 03/11/2026
Runtipi is a personal homeserver orchestrator. Prior to 4.8.0, an unauthenticated attacker can reset the operator (admin) password when a password-reset request is active, resulting in full account takeover. The endpoint POST /api/auth/reset-password is exposed without authentication/authorization checks. During the 15-minute reset window, any remote user can set a new operator password and log in as admin. This vulnerability is fixed in 4.8.0.
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Analysis
by VulDB Data Team • 03/17/2026
The vulnerability described in CVE-2026-31881 affects Runtipi, a personal homeserver orchestrator software that enables users to manage and deploy containerized applications on their local networks. This system serves as a centralized management interface for home server environments, making it a critical component for users who rely on local automation and application orchestration. The flaw represents a severe authentication bypass issue that fundamentally compromises the security model of the platform, as it allows unauthorized remote attackers to gain administrative privileges without any prior credentials or authorization.
The technical implementation of this vulnerability resides in the authentication reset mechanism of the application's API endpoints. Specifically, the POST /api/auth/reset-password endpoint lacks proper authentication and authorization checks, creating an authentication gap that persists for exactly 15 minutes after any password reset request is initiated. This window of opportunity enables attackers to exploit the system by simply sending a request to this endpoint with a new password value, effectively bypassing all normal authentication procedures. The vulnerability directly maps to CWE-306, which addresses missing authentication for critical functions, and represents a classic case of inadequate access control implementation where the system fails to verify the identity of users attempting to perform privileged operations.
The operational impact of this vulnerability is significant and potentially devastating for affected users. An unauthenticated attacker with network access to the Runtipi system can immediately take full control of the administrator account, gaining complete access to all system configurations, deployed applications, and user data managed through the platform. This account takeover capability allows for arbitrary modifications to the system, potential data exfiltration, and the ability to install malicious software or backdoors. The 15-minute window provides attackers with sufficient time to exploit the vulnerability without requiring complex reconnaissance or social engineering tactics, making this a particularly dangerous flaw for home server administrators who may not continuously monitor their systems for such attacks.
The mitigation strategy for this vulnerability involves upgrading to version 4.8.0 or later, which implements proper authentication checks for the password reset endpoint. Organizations and individuals using Runtipi should immediately apply this update to protect their systems. Additional defensive measures include implementing network-level access controls to restrict access to the Runtipi API endpoints, monitoring for unauthorized access attempts, and ensuring that the system is not exposed to untrusted networks. From a broader security perspective, this vulnerability demonstrates the importance of applying the principle of least privilege and ensuring that all critical system functions require proper authentication before execution, aligning with ATT&CK technique T1078.004 for Valid Accounts and T1566.001 for Phishing for Information. System administrators should also consider implementing additional security monitoring to detect anomalous password reset activities and establish proper network segmentation to limit exposure of such critical endpoints to external networks.