Impact
This allows anyone that can connect to the server to forge a LoginPacket with manipulated JWT token allowing impersonation as any Bedrock user. Unless credentials are saved in your configuration, online mode is not affected as users are still required to log in separately. If your credentials are saved, there is no risk of exposing your email or password.
Patches
This was patched as part of GeyserMC/Geyser@b954150 and GeyserMC/Geyser@ab2f5b3. if your Geyser version is 1.4.2-SNAPSHOT or later, the issue has been addressed on your build.
Workarounds
Geyser strongly recommends updating to fix this issue. If this isn't possible:
- Use online mode and don't save credentials in your Geyser configuration
- Use an additional authentication method on the Java server
References
This was disclosed to us by a staff member over at Hive; you can read their disclosure here: https://updates.playhive.com/weekend-maintenance-disclosure-2kJMaY
For more information
If you have any questions or comments about this advisory:
References
Impact
This allows anyone that can connect to the server to forge a LoginPacket with manipulated JWT token allowing impersonation as any Bedrock user. Unless credentials are saved in your configuration, online mode is not affected as users are still required to log in separately. If your credentials are saved, there is no risk of exposing your email or password.
Patches
This was patched as part of GeyserMC/Geyser@b954150 and GeyserMC/Geyser@ab2f5b3. if your Geyser version is
1.4.2-SNAPSHOTor later, the issue has been addressed on your build.Workarounds
Geyser strongly recommends updating to fix this issue. If this isn't possible:
References
This was disclosed to us by a staff member over at Hive; you can read their disclosure here: https://updates.playhive.com/weekend-maintenance-disclosure-2kJMaY
For more information
If you have any questions or comments about this advisory:
References