Security readout for executives and security teams
Plain-English summary
This AMD Secure Processor issue can cause a system-level denial of service if the vulnerable SMI mailbox checksum handling reads outside expected bounds and triggers a data abort. The business impact is availability disruption, not data theft, based on the provided sources.
Executive priority
Treat this as a high-priority availability risk for AMD fleets, especially systems supporting critical operations. Urgency depends on whether your OEM firmware is affected and whether remediation is available for deployed platforms.
Technical view
CVE-2021-46749 is a CWE-125 out-of-bounds read in AMD Secure Processor SMI mailbox checksum calculation. AMD describes insufficient bounds checking that may trigger a data abort, causing potential denial of service. CVSS 3.1 is 7.5 with availability impact only.
Likely exposure
Exposure is tied to AMD AGESA-based platforms in the listed Ryzen, Threadripper, and Athlon families. The bundle does not provide exact vulnerable AGESA or BIOS versions, so platform and OEM firmware mapping is required.
Exploitation context
The provided bundle does not show CISA KEV listing or cited evidence of active exploitation. It describes a potential denial-of-service condition, not confidentiality or integrity compromise.
Researcher notes
The source data is limited: it names processor families and AGESA context but not precise vulnerable versions or fixed firmware levels. Avoid assuming exploitability beyond the reported out-of-bounds read leading to data abort and denial of service.
Mitigation direction
- Review AMD-SB-4001 and relevant OEM firmware guidance.
- Inventory AMD systems using the listed processor families.
- Map current BIOS or AGESA versions against vendor guidance.
- Prioritize firmware remediation for availability-critical endpoints and servers.
- Track OEM advisories when AMD guidance is not directly actionable.
Validation and detection
- Confirm CPU family and platform firmware version for each AMD system.
- Check whether each platform appears in AMD-SB-4001 or OEM advisories.
- Verify applied BIOS or firmware updates through endpoint inventory.
- Monitor affected systems for unexplained crashes or availability events.
- Document unknown firmware mappings as unresolved exposure.
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.
CWE-125: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-46749 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
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://www.amd.com/en/corporate/product-security/bulletin/AMD-SB-4001CVE 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.
Out-of-bounds Read
Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.