CVE-2021-26387
No known exploitation. EPSS puts it in the 3rd percentile. No fix published yet.
What to do
No fixed build or workaround is published yet. Limit exposure and watch for a patch.
What it is
From the CVE record
Insufficient access controls in ASP kernel may allow a privileged attacker with access to AMD signing keys and the BIOS menu or UEFI shell to map DRAM regions in protected areas, potentially leading to a loss of platform integrity.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.1% chance of exploitation activity in the next 30 days, which ranks it in the 3rd percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
4 events over 78 days, from the signal feeds we watch.
- Record updated
- Publishedweakness classified, att&ck mapped
Affected products
- AMD EPYC™ 7001 Series ProcessorsHardware Firmware
- AMD EPYC™ 7002 Series ProcessorsHardware Firmware
- AMD EPYC™ 7003 Series ProcessorsHardware Firmware
- AMD EPYC™ 9004 Series ProcessorsHardware Firmware
- AMD Ryzen™ 3000 Series Desktop ProcessorsHardware Firmware
- AMD Ryzen™ 5000 Series Desktop ProcessorsHardware Firmware
- AMD Ryzen™ 5000 Series Desktop Processor with Radeon™ GraphicsHardware Firmware
- AMD Ryzen™ 7000 Series Desktop ProcessorsHardware Firmware
And 23 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:N/I:L/A:L
Scored 3.9 by NVD.
How it is reached
- Attack Vector LocalRequires local access to the vulnerable system (e.g. local login, malicious file)
- Attack Complexity HighRequires specific conditions like a race condition or non-default configuration
- Privileges Required HighRequires admin or elevated privileges
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity LowData modification is possible but limited in scope or consequence
- Availability LowReduced performance or intermittent disruption of service
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
Watch the software you run.
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