Privilege escalation in Tianocore EDK II

Published: 2021-06-30

Risk	Low
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2021-28211 CVE-2019-14584
CWE-ID	CWE-122 CWE-476
Exploitation vector	Local
Public exploit	N/A
Vulnerable software	edk2 Hardware solutions / Firmware
Vendor	TianoCore

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

1) Heap-based buffer overflow

EUVDB-ID: #VU54481

Risk: Low

CVSSv4.0: 5.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-28211

CWE-ID: CWE-122 - Heap-based Buffer Overflow

Exploit availability: No

Description

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

The vulnerability exists due to a boundary error within the LzmaUefiDecompressGetInfo() function. A local user can run a specially crafted program to trigger a heap-based buffer overflow and execute arbitrary code with elevated privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

edk2: edk2-stable201808 - UDK2018

CPE2.3

External links

https://bugzilla.tianocore.org/show_bug.cgi?id=1816

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.

2) NULL pointer dereference

EUVDB-ID: #VU54483