Privilege escalation via exposed UEFI password hashes
Published Sep 3, 2026 · Updated Sep 3, 2026
Credential exposure in SysPasswordDxe in Insyde Software InsydeH2O allows local users to obtain BIOS password hashes. The driver exposes user and administrator password hashes through runtime-accessible UEFI variables whose permissions do not restrict low-privileged reads. Low-privileged local access is required; the exposed hashes enable privilege escalation without a reported ability to interrupt service.
Summary
What happened
Credential exposure in SysPasswordDxe in Insyde Software InsydeH2O allows local users to obtain BIOS password hashes. The driver exposes user and administrator password hashes through runtime-accessible UEFI variables whose permissions do not restrict low-privileged reads. Low-privileged local access is required; the exposed hashes enable privilege escalation without a reported ability to interrupt service.
The record
- CVE
- CVE-2021-43613
- Published
- Sep 3, 2026
- Updated
- Sep 3, 2026
- Vendor
- Insyde Software
- Product
- InsydeH2O UEFI BIOS
- Classifications
- CWE-732, T1552
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 3, 2026CVE publishedPublication date reported by the CVE source.
- Sep 3, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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- Affected versionversion=See in the Solution
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What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Technologies
Your stack
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Your stack
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