SMM code execution via unchecked destination pointer
Published Jul 23, 2021 · Updated Aug 4, 2024
Privilege escalation in ASRock 4X4 BOX-R1000 firmware before P1.40 allows local users to execute code in SMM. The SmiVariable driver's SMI 0xEF handler passes attacker-controlled RSI-based pointers to SmmGetVariable without checking whether the destination lies in SMRAM. Exploitation requires kernel-level access to trigger the software SMI, after which arbitrary SMRAM writes bypass operating-system and hypervisor protections.
Summary
What happened
Privilege escalation in ASRock 4X4 BOX-R1000 firmware before P1.40 allows local users to execute code in SMM. The SmiVariable driver's SMI 0xEF handler passes attacker-controlled RSI-based pointers to SmmGetVariable without checking whether the destination lies in SMRAM. Exploitation requires kernel-level access to trigger the software SMI, after which arbitrary SMRAM writes bypass operating-system and hypervisor protections.
The record
- CVE
- CVE-2020-14032
- Published
- Jul 23, 2021
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-269, T1068
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Jul 23, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- SMM write-primitive and HVCI-bypass proof-of-concept videoproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo