CVE-2024-34701

CreateWiki is Mirahezes MediaWiki extension for requesting & creating wikis. It is possible for users to be considered as the requester of a specific wiki request if their local user ID on any wiki in a wiki farm matches the local ID of the requester at the wiki where the wiki request was made. This allows them to go to that request entrys on Special:RequestWikiQueue on the wiki where their local user ID matches and take any actions that the wiki requester is allowed to take from there.

Commit 02e0f298f8d35155c39aa74193cb7b867432c5b8 fixes the issue. Important note about the fix: This vulnerability has been fixed by disabling access to the REST API and special pages outside of the wiki configured as the global wiki in $wgCreateWikiGlobalWiki in a users MediaWiki settings.

As a workaround, it is possible to disable the special pages outside of ones own global wiki by doing something similar to miraheze/mw-config commit e5664995fbb8644f9a80b450b4326194f20f9ddc that is adapted to ones own setup. As for the REST API, before the fix, there wasnt any REST endpoint that allowed one to make writes. Regardless, it is possible to also disable it outside of the global wiki by using $wgCreateWikiDisableRESTAPI and $wgConf in the configuration for ones own wiki farm..

Weakness

The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions.

Extended Description

Assuming a user with a given identity, authorization is the process of determining whether that user can access a given resource, based on the user’s privileges and any permissions or other access-control specifications that apply to the resource. When access control checks are incorrectly applied, users are able to access data or perform actions that they should not be allowed to perform. This can lead to a wide range of problems, including information exposures, denial of service, and arbitrary code execution.

Potential Mitigations

• Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) [REF-229] to enforce the roles at the appropriate boundaries.
• Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
• Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
• For example, consider using authorization frameworks such as the JAAS Authorization Framework [REF-233] and the OWASP ESAPI Access Control feature [REF-45].
• For web applications, make sure that the access control mechanism is enforced correctly at the server side on every page. Users should not be able to access any unauthorized functionality or information by simply requesting direct access to that page.
• One way to do this is to ensure that all pages containing sensitive information are not cached, and that all such pages restrict access to requests that are accompanied by an active and authenticated session token associated with a user who has the required permissions to access that page.

References

• https://github.com/miraheze/CreateWiki/commit/02e0f298f8d35155c39aa74193cb7b867432c5b8
• https://github.com/miraheze/CreateWiki/security/advisories/GHSA-89fx-77w7-rc64
• https://github.com/miraheze/mw-config/commit/1798e53901a202b62edab32f8bcd5c6b9e574191
• https://github.com/miraheze/mw-config/commit/e5664995fbb8644f9a80b450b4326194f20f9ddc
• https://issue-tracker.miraheze.org/T12011
• https://issue-tracker.miraheze.org/T12102