#VU53836 Deserialization of Untrusted Data in BdLib - CVE-2021-33806

Vulnerability identifier: #VU53836

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-33806

CWE-ID: CWE-502

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
BdLib
Universal components / Libraries / Libraries used by multiple products

Vendor: bdew-minecraft

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to insecure input validation when processing serialized data in the "ObjectInputStream.readObject()" function. A remote attacker can pass specially crafted data to the application and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

BdLib: 1.16.1.6

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External links
https://bdew.net
https://github.com/bdew-minecraft/bdlib/commit/447210530ceec72fb3374efecb0930ed359d2297
https://www.curseforge.com/minecraft/mc-mods/bdlib/files/3331330
https://vuln.ryotak.me/advisories/46

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.