CVE Vulnerabilities

CVE-2021-33790

Deserialization of Untrusted Data

Published: May 31, 2021 | Modified: Nov 21, 2024
CVSS 3.x
9.8
CRITICAL
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
7.5 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu

The RebornCore library before 4.7.3 allows remote code execution because it deserializes untrusted data in ObjectInputStream.readObject as part of reborncore.common.network.ExtendedPacketBuffer. An attacker can instantiate any class on the classpath with any data. A class usable for exploitation might or might not be present, depending on what Minecraft modifications are installed.

Weakness

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

Affected Software

Name Vendor Start Version End Version
Reborncore Techreborn * 3.13.8 (including)
Reborncore Techreborn 3.19.0 (including) 3.19.5 (excluding)
Reborncore Techreborn 4.2.0 (including) 4.2.10 (excluding)
Reborncore Techreborn 4.7.0 (including) 4.7.3 (excluding)

Potential Mitigations

  • Make fields transient to protect them from deserialization.
  • An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.

References