CVE-2021-38576
CVE-2021-38576 is a high-severity vulnerability in Tianocore Edk2 with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 7.8
- EPSS exploit prediction: 1% (63rd percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Tianocore Edk2
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2021-38576?
- 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.
- How severe is CVE-2021-38576?
- CVE-2021-38576 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2021-38576 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-38576?
- CVE-2021-38576 primarily affects Tianocore Edk2. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-38576?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-38576 published?
- CVE-2021-38576 was published on 2022-01-03 and last updated on 2026-06-17.
References
- https://bugzilla.tianocore.org/show_bug.cgi?id=3499
- https://lists.debian.org/debian-lts-announce/2025/06/msg00007.html
Affected products (12)
- cpe:2.3:a:tianocore:edk2:201808:*:*:*:*:*:*:*
- cpe:2.3:a:tianocore:edk2:201811:*:*:*:*:*:*:*
- cpe:2.3:a:tianocore:edk2:201903:*:*:*:*:*:*:*
- cpe:2.3:a:tianocore:edk2:201905:*:*:*:*:*:*:*
- cpe:2.3:a:tianocore:edk2:201908:*:*:*:*:*:*:*
- cpe:2.3:a:tianocore:edk2:201911:*:*:*:*:*:*:*
- cpe:2.3:a:tianocore:edk2:202002:*:*:*:*:*:*:*
- cpe:2.3:a:tianocore:edk2:202005:*:*:*:*:*:*:*
- cpe:2.3:a:tianocore:edk2:202008:*:*:*:*:*:*:*
- cpe:2.3:a:tianocore:edk2:202011:*:*:*:*:*:*:*
- cpe:2.3:a:tianocore:edk2:202102:*:*:*:*:*:*:*
- cpe:2.3:a:tianocore:edk2:202105:*:*:*:*:*:*:*
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