SMM privilege escalation via HddPassword out-of-bounds write
Published Feb 3, 2022 · Updated Aug 11, 2026
Out-of-bounds write in HddPassword in InsydeH2O kernel 5.1 through 5.5 allows local users to escalate privileges to SMM. The firmware component writes fixed or predictable data outside its intended bounds into protected SMRAM; the precise faulty operation is not publicly disclosed. Exploitation requires high-privilege local code execution on an affected device and grants control beneath the operating system.
Summary
What happened
Out-of-bounds write in HddPassword in InsydeH2O kernel 5.1 through 5.5 allows local users to escalate privileges to SMM. The firmware component writes fixed or predictable data outside its intended bounds into protected SMRAM; the precise faulty operation is not publicly disclosed. Exploitation requires high-privilege local code execution on an affected device and grants control beneath the operating system.
The record
- CVE
- CVE-2021-43615
- Published
- Feb 3, 2022
- Updated
- Aug 11, 2026
- Vendor
- Siemens
- Product
- SIMATIC IPC477E PRO
- Classifications
- CWE-787, T1068
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Feb 3, 2022CVE publishedPublication date reported by the CVE source.
- Aug 11, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <V21.01.17
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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