#VU60276 Buffer overflow in FwBlockServiceSmm - CVE-2021-33627

Vulnerability identifier: #VU60276

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-2021-33627

CWE-ID: CWE-119

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
FwBlockServiceSmm
Hardware solutions / Drivers

Vendor: Insyde Software

Description

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

The vulnerability exists due to a boundary error in SMM (System Management Mode) branch that registers a SWSMI handler. A remote attacker can trigger memory corruption 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

FwBlockServiceSmm: before 5.0: 05.08.29

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External links
https://www.insyde.com/security-pledge

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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.