Security readout for executives and security teams
Plain-English summary
This AMD firmware-related issue could let a local attacker corrupt sensitive memory if they already have a compromised ABL and UApp. The main business risk is system integrity or availability loss on affected 3rd Gen AMD EPYC platforms, not data disclosure.
Executive priority
Treat as high priority for EPYC-based infrastructure that supports critical operations. Urgency is driven by potential integrity and availability impact, but available evidence does not indicate active exploitation.
Technical view
CVE-2021-26397 is insufficient address validation in AMD AGESA for 3rd Gen AMD EPYC. CVSS 3.1 is 7.1 with local access, low complexity, low privileges, no user interaction, and high integrity and availability impact.
Likely exposure
Exposure is most likely on systems using 3rd Gen AMD EPYC platforms with affected AGESA firmware versions. The bundle says versions are various and does not identify exact firmware builds.
Exploitation context
The provided sources do not show CISA KEV listing or active exploitation. The described attack requires local low-privileged access and a compromised ABL and UApp, so it is not presented as a remote, unauthenticated issue.
Researcher notes
No CWE is listed in the bundle. The CVSS vector indicates no confidentiality impact, unchanged scope, and high integrity and availability impact. Affected version detail and concrete patch mapping are incomplete in the provided data.
Mitigation direction
- Review AMD-SB-3001 and relevant server OEM advisories for affected firmware guidance.
- Apply applicable BIOS, firmware, or AGESA updates through supported vendor channels.
- Restrict local and administrative access on potentially affected EPYC systems.
- Prioritize remediation for critical workloads where availability or platform integrity is business-critical.
Validation and detection
- Inventory 3rd Gen AMD EPYC systems across servers and cloud-adjacent infrastructure.
- Compare platform BIOS and AGESA levels against AMD-SB-3001 and OEM guidance.
- Confirm whether compensating access controls limit local low-privileged attacker opportunities.
- Track CISA KEV and vendor advisories for any change in exploitation status.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2021-26397 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H1.85.2Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.1HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://www.amd.com/en/corporate/product-security/bulletin/AMD-SB-3001CVE reference · vendor-advisory
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.