CVE-2026-53527 in LeafWiki
Summary
by MITRE • 08/22/2026
LeafWiki is a self-hosted wiki. Versions 0.1.0 through 0.10.0 have a privilege escalation vulnerability in the user update API. An authenticated user could update their own account role and escalate privileges from a regular user, such as `viewer`, to `admin`. Exploitation requires a valid authenticated LeafWiki user account. Instances without public registration and with only trusted users are at lower practical risk. Users should update to version 0.10.1 or greater. Until a patch is available, operators should restrict account creation and ensure that only trusted users have accounts on affected LeafWiki instances. If possible, access to the user update API should be restricted to trusted users or administrators only.
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Analysis
by VulDB Data Team • 08/22/2026
LeafWiki versions 0.1.0 through 0.10.0 contain a critical privilege escalation vulnerability within its user management subsystem, specifically affecting the API endpoint responsible for updating user account details. This flaw allows an authenticated attacker with low-privilege access to modify their own role assignment field in the backend database or application logic without proper authorization checks. By manipulating this parameter during a standard profile update request, a regular user can elevate their permissions from a restricted role such as viewer to that of an administrator. The vulnerability stems from insufficient validation on the server side regarding which fields are permitted for self-modification, effectively bypassing the intended access control mechanisms designed to separate administrative functions from end-user operations.
The operational impact of this flaw is severe, as it grants full administrative control over the LeafWiki instance to any authenticated user who can exploit the API endpoint. Once elevated to an admin role, the attacker gains unrestricted access to all wiki content, including sensitive documents and configuration settings. They can create new administrator accounts, delete existing users, modify system configurations, or potentially execute further attacks depending on how the underlying infrastructure is integrated with other services. This compromises the confidentiality, integrity, and availability of the entire platform, as the attacker effectively becomes the owner of the application environment without needing to exploit additional vulnerabilities for initial access beyond valid authentication credentials.
From a classification perspective, this vulnerability aligns with CWE-269 Improper Privilege Management, where an actor is able to elevate privileges by exploiting flaws in role-based access control logic. It also maps to MITRE ATT&CK technique T1078 Valid Accounts, as the exploitation relies on legitimate credentials rather than unauthorized intrusion methods initially. The lack of checks preventing users from modifying their own privilege levels represents a fundamental failure in enforcing least-privilege principles within the application architecture. This type of flaw is particularly dangerous because it does not require complex injection techniques or remote code execution vectors; instead, it leverages standard authenticated interactions to achieve high-level system compromise.
Mitigation strategies focus primarily on upgrading the software infrastructure immediately. Operators must update LeafWiki to version 0.10.1 or any subsequent release where this privilege escalation vector has been patched through proper input validation and authorization checks in the user update API. For environments that cannot be updated immediately due to operational constraints, temporary mitigations include disabling public registration entirely to ensure only pre-vetted individuals hold accounts. Additionally, administrators should implement network-level restrictions if possible, limiting direct access to the user management endpoints to trusted internal networks or specific IP ranges. Regular auditing of account roles and monitoring for unusual privilege changes can also help detect exploitation attempts early before significant damage occurs.