CVE-2021-38576: tianocore edk2
Vulnerability summary
CVE-2021-38576 is a high (CVSS 7.8) vulnerability in tianocore edk2. EPSS estimates a 1.25% chance of exploitation in the next 30 days, higher than 69.4% of scored vulnerabilities.
Severe, CVSS 7.5 (NVD); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 1Timeline
- 03-01-2022PublishedVulnerability first disclosed.
- 03-11-2025Last modifiedVulnerability information updated.
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 metrics
4 scores · 3 sources · 2 versions- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- NVDNIST7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
1.25%
Chance of exploitation in the next 30 days
Percentile
69%
Versus all other CVEs
30-day change
Increase +0.09 pp
From 1.17% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Debian1 product
- edk2< 2021.11-1
Tianocore1 product
- edk2201808 | 201811 | 201903 | 201905 | 201908 | 201911 | 202002 | 202005 | 202008 | 202011 | 202102 | 202105
Ubuntu1 product
- edk2All versions (No fix recorded)
3 vendors · 3 products
References
5 links- bugzilla.tianocore.org/show_bug.cgi?id=3499X Refsource MISCIssue TrackingPermissions RequiredThird Party Advisory
