Arbitrary code execution via NVRAM stack overflow
Published Feb 16, 2022 · Updated Aug 4, 2024
Stack buffer overflow in HP PC UEFI firmware allows local users to execute arbitrary code in a DXE runtime application. The CheckBatterySafety function reuses an attacker-inflated NVRAM variable length when GetVariable writes BatterySafetyMode into a one-byte stack buffer. Local privileged access is required to alter the variables; successful exploitation reaches firmware execution and can persist across system boots.
Summary
What happened
Stack buffer overflow in HP PC UEFI firmware allows local users to execute arbitrary code in a DXE runtime application. The CheckBatterySafety function reuses an attacker-inflated NVRAM variable length when GetVariable writes BatterySafetyMode into a one-byte stack buffer. Local privileged access is required to alter the variables; successful exploitation reaches firmware execution and can persist across system boots.
The record
- CVE
- CVE-2021-39301
- Published
- Feb 16, 2022
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- T1068, T1542.001
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Feb 16, 2022CVE 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
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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.
Public exploit references
- Binarly NVRAM stack-overflow exploitation stepsproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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