CVE-2026-92776 in Wiki.js
Summary
by MITRE • 09/16/2026
Wiki.js through 2.5.314 fails to require path separators when matching START and END page rules, allowing attackers to access pages sharing a prefix with authorized folders. Users granted access to a folder can read and modify unrelated pages with matching prefixes, bypassing intended access controls.
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Analysis
by VulDB Data Team • 09/16/2026
The vulnerability identified in Wiki.js versions up through 2.5.314 represents a critical failure in the application's path resolution logic regarding access control enforcement. This flaw specifically affects the mechanism used to match START and END page rules within the system's permission configuration framework. In secure web applications, particularly those managing hierarchical content like wikis, it is standard practice for authorization checks to enforce strict boundary conditions when evaluating user permissions against resource paths. The intended behavior requires that a path segment be fully delimited by separators such as forward slashes or backslashes to ensure precise matching of directory structures. However, the implementation in these versions of Wiki.js lacks this necessary validation step during the rule evaluation process. Consequently, the system treats partial string matches as valid authorization grants rather than requiring exact structural alignment.
This technical deficiency allows attackers who have been granted access to a specific folder or page prefix to exploit the loose matching logic for unauthorized lateral movement within the wiki structure. For instance if an attacker is authorized to view content under the path /projects/alpha, the flawed matcher may also grant them read and write access to pages located at paths such as /projects/alphabeta or /public/projects/alpha_backup because these paths share the initial character sequence with the authorized folder. This bypasses the intended isolation between different sections of the wiki that are governed by distinct permission sets. The vulnerability effectively collapses the hierarchical security model into a flat prefix-based access control list, undermining the principle of least privilege and allowing users to interact with resources they should not be able to reach based on their assigned roles.
The operational impact of this flaw is significant for organizations relying on Wiki.js for sensitive documentation or collaborative knowledge management where strict compartmentalization is required. Users with limited privileges can discover hidden pages that were intended to be restricted, potentially exposing confidential information such as internal project details, proprietary code snippets, or administrative credentials stored in wiki entries. Furthermore the ability to modify these unrelated pages introduces risks of data integrity compromise and potential supply chain attacks if attackers inject malicious content into trusted documentation sources. This could lead to social engineering successes against other users who trust the wiki's accuracy or facilitate further exploitation vectors such as cross-site scripting if user input is rendered without proper sanitization in those exposed areas.
From a classification perspective this vulnerability aligns with CWE-284 Improper Access Control and specifically relates to path traversal concepts where insufficient boundary validation allows access beyond intended directories although it manifests here through string prefix matching rather than traditional directory climbing techniques like dot-dot-slash sequences. In the context of the MITRE ATT&CK framework this behavior facilitates unauthorized data exfiltration and potentially privilege escalation depending on the specific permissions granted within those matched prefixes. It represents a fundamental flaw in how the application interprets resource identifiers for security policy enforcement, highlighting the importance of strict string delimiting when implementing role-based access control systems that rely on hierarchical path structures.
To mitigate this vulnerability organizations must upgrade to version 2.5.315 or later where the developers have corrected the path matching logic to enforce proper separator requirements. Until an update can be applied administrators should review existing permission rules and restrict broad prefix-based grants by defining more specific paths that include explicit delimiters for all sub-resources. Additionally implementing strict input validation on any custom plugins or extensions that interact with page metadata is advisable as a defense-in-depth measure. Regular audits of access control configurations are recommended to ensure no overly permissive rules exist that could be exploited via similar prefix matching techniques in other parts of the application architecture.