Lemmy up to 0.19.0 API report improper authorization

Summaryinfo

A vulnerability labeled as critical has been found in Lemmy up to 0.19.0. Affected by this vulnerability is an unknown functionality of the file /api/v3/private_message/report of the component API. Executing a manipulation can lead to improper authorization. This vulnerability is registered as CVE-2024-23649. It is possible to launch the attack remotely. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical was found in Lemmy up to 0.19.0. This vulnerability affects an unknown part of the file /api/v3/private_message/report of the component API. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality. CVE summarizes:

Lemmy is a link aggregator and forum for the fediverse. Starting in version 0.17.0 and prior to version 0.19.1, users can report private messages, even when they're neither sender nor recipient of the message. The API response to creating a private message report contains the private message itself, which means any user can just iterate over message ids to (loudly) obtain all private messages of an instance. A user with instance admin privileges can also abuse this if the private message is removed from the response, as they're able to see the resulting reports. Creating a private message report by POSTing to `/api/v3/private_message/report` does not validate whether the reporter is the recipient of the message. lemmy-ui does not allow the sender to report the message; the API method should likely be restricted to accessible to recipients only. The API response when creating a report contains the `private_message_report_view` with all the details of the report, including the private message that has been reported: Any authenticated user can obtain arbitrary (untargeted) private message contents. Privileges required depend on the instance configuration; when registrations are enabled without application system, the privileges required are practically none. When registration applications are required, privileges required could be considered low, but this assessment heavily varies by instance. Version 0.19.1 contains a patch for this issue. A workaround is available. If an update to a fixed Lemmy version is not immediately possible, the API route can be blocked in the reverse proxy. This will prevent anyone from reporting private messages, but it will also prevent exploitation before the update has been applied.

The weakness was published 01/24/2024 as GHSA-r64r-5h43-26qv. The advisory is available at github.com. This vulnerability was named CVE-2024-23649 since 01/19/2024. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1548.002 by the MITRE ATT&CK project.

Upgrading to version 0.19.1 eliminates this vulnerability. Applying the patch bc32b408b523b9b64aa57b8e47748f96cce0dae5 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

• Lemmy

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13
• 0.14
• 0.15
• 0.16
• 0.17
• 0.18
• 0.19.0

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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