CVE-2021-37632

Deserialization of Untrusted Data in com.supermartijn642.configlib.ConfigSyncPacket

Description

SuperMartijn642's Config Lib is a library used by a number of mods for the game Minecraft. The versions of SuperMartijn642's Config Lib between 1.0.4 and 1.0.8 are affected by a vulnerability and can be exploited on both servers and clients. Using SuperMartijn642's Config Lib, servers will send a packet to clients with the server's config values. In order to read `enum` values from the packet data, `ObjectInputStream#readObject` is used. `ObjectInputStream#readObject` will instantiate a class based on the input data. Since, the packet data is not validated before `ObjectInputStream#readObject` is called, an attacker can instantiate any class by sending a malicious packet. If a suitable class is found, the vulnerability can lead to a number of exploits, including remote code execution. Although the vulnerable packet is typically only send from server to client, it can theoretically also be send from client to server. This means both clients and servers running SuperMartijn642's Config Lib between 1.0.4 and 1.0.8 are vulnerable. The vulnerability has been patched in SuperMartijn642's Config lib 1.0.9. Both, players and server owners, should update to 1.0.9 or higher.

Category

8.1
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.86% Top 20%
Third-Party Advisory github.com
Affected: SuperMartijn642 SuperMartijn642sConfigLib
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-37632?
CVE-2021-37632 has been scored as a high severity vulnerability.
How to fix CVE-2021-37632?
To fix CVE-2021-37632, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-37632 being actively exploited in the wild?
It is possible that CVE-2021-37632 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-37632?
CVE-2021-37632 affects SuperMartijn642 SuperMartijn642sConfigLib.
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