#VU75395 Out-of-bounds write in edk2 - CVE-2021-38578

Vulnerability identifier: #VU75395

Vulnerability risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-38578

CWE-ID: CWE-787

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
edk2
Hardware solutions / Firmware

Vendor: TianoCore

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a boundary error in MdeModulePkg/Core/PiSmmCore/PiSmmCore.c. A local user trigger an out-of-bounds write and execute arbitrary code with elevated privileges.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

edk2: edk2-stable201808 - UDK2018

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External links
https://bugzilla.tianocore.org/show_bug.cgi?id=3387
https://github.com/tianocore/edk2/commit/cab1f02565d3b29081dd21afb074f35fdb4e1fd6

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

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