CVE-2021-39177
Versions of Geyser prior to 1.4.2-SNAPSHOT allow anyone that can connect to the server to forge a LoginPacket with manipulated JWT token allowing impersonation as any user.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.43%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Geyser is a bridge between Minecraft: Bedrock Edition and Minecraft: Java Edition. Versions of Geyser prior to 1.4.2-SNAPSHOT allow anyone that can connect to the server to forge a LoginPacket with manipulated JWT token allowing impersonation as any user. Version 1.4.2-SNAPSHOT contains a patch for the issue. There are no known workarounds aside from upgrading.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.43% probability · 72th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-287
- Affected
- geysermc/geyser
- Source
- security-advisories@github.com
References
- https://github.com/GeyserMC/Geyser/commit/b9541505af68ac7b7c093206ac7b1ba88957a5a6Patch, Third Party Advisory
- https://github.com/GeyserMC/Geyser/security/advisories/GHSA-h77f-xxx7-4858Patch, Third Party Advisory
- https://updates.playhive.com/weekend-maintenance-disclosure-2kJMaYThird Party Advisory
- https://github.com/GeyserMC/Geyser/commit/b9541505af68ac7b7c093206ac7b1ba88957a5a6Patch, Third Party Advisory
- https://github.com/GeyserMC/Geyser/security/advisories/GHSA-h77f-xxx7-4858Patch, Third Party Advisory
- https://updates.playhive.com/weekend-maintenance-disclosure-2kJMaYThird Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.