CVE-2021-33790

Description

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.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 5.43% Top 15%
Third-Party Advisory github.com Third-Party Advisory ryotak.me Third-Party Advisory curseforge.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://www.curseforge.com/minecraft/mc-mods/reborncore third party advisory product
https://vuln.ryotak.me/advisories/45 third party advisory
https://github.com/TechReborn/RebornCore/security/advisories/GHSA-r7pg-4xrf-7mrm third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-33790?
CVE-2021-33790 has been scored as a critical severity vulnerability.
How to fix CVE-2021-33790?
To fix CVE-2021-33790, 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-2021-33790 being actively exploited in the wild?
It is possible that CVE-2021-33790 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~5% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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