#VU53387 Input validation error in MBUX Infotainment System - CVE-2021-23909

Vulnerability identifier: #VU53387

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-2021-23909

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
MBUX Infotainment System
Client/Desktop applications / Other client software

Vendor: Mercedes-Benz

Description

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

The vulnerability exists in HERMES 2.1 on Mercedes-Benz vehicles due to insufficient validation of user-supplied input in the SH2 MCU. A remote attacker can pass specially crafted input and execute arbitrary code on the target system.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

MBUX Infotainment System: 2021

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External links
https://keenlab.tencent.com/en/2021/05/12/Tencent-Security-Keen-Lab-Experimental-Security-Assessment-on-Mercedes-Benz-Cars/
https://keenlab.tencent.com/en/whitepapers/Mercedes_Benz_Security_Research_Report_Final.pdf
https://media.daimler.com/marsMediaSite/en/instance/ko.xhtml?oid=49946866

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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.