CVE-2021-39177 – org.geysermc:connector

Package

Manager: maven
Name: org.geysermc:connector
Vulnerable Version: >=0 <=1.4.1-snapshot

Severity

Level: High

CVSS v3.1: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS v4.0: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

EPSS: 0.00352 pctl0.56897

Details

User impersonation due to incorrect handling of the login JWT ### 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 https://github.com/GeyserMC/Geyser/commit/b9541505af68ac7b7c093206ac7b1ba88957a5a6 and https://github.com/GeyserMC/Geyser/commit/ab2f5b326fe590e09167e8b45b4b165ac06ecd13. 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: * Come talk to us over on our [Discord](https://discord.gg/geysermc) server in the [#development](https://discord.com/channels/613163671870242838/613170125696270357) channel

Metadata

Created: 2021-09-07T23:04:04Z
Modified: 2021-09-07T14:04:02Z
Source: MANUAL
CWE IDs: ["CWE-287"]
Alternative ID: GHSA-h77f-xxx7-4858
Finding: F006
Auto approve: 1