High severity · published Jan 3, 2022
CVE-2021-38576
A BIOS bug in firmware for a particular PC model leaves the Platform authorization value empty
7.5
CVSS
1.3%
EPSS
No
On KEV
Description
A BIOS bug in firmware for a particular PC model leaves the Platform authorization value empty. This can be used to permanently brick the TPM in multiple ways, as well as to non-permanently DoS the system.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.3% · higher than 69% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ED
Edk2 · Tianocore
201808; 201811; 201903; 201905; 201908; 201911; +6 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-38576
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-38576
Issue Tracking
https://bugzilla.tianocore.org/show_bug.cgi?id=3499
lists.debian.org
https://lists.debian.org/debian-lts-announce/2025/06/msg00007.html
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