Security readout for executives and security teams
Plain-English summary
CVE-2021-21573 is a high-severity Dell BIOSConnect buffer overflow. A malicious local administrator could potentially run arbitrary code and bypass UEFI restrictions. Business risk is concentrated on Dell endpoints where BIOSConnect is present and local administrator access is broad.
Executive priority
Treat as a high-priority firmware exposure, especially in environments with many Dell endpoints or weak local admin controls. It is not shown as actively exploited in the provided sources, but impact could be severe if prerequisites are met.
Technical view
The issue is a CWE-121 buffer overflow in Dell BIOSConnect. CVSS 3.1 is 7.2 with local attack vector, high complexity, high privileges, user interaction, changed scope, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is limited to Dell BIOSConnect, but the provided sources do not identify affected models or versions. Organizations need Dell asset inventory and the Dell advisory to determine which systems are in scope.
Exploitation context
The provided bundle does not show CISA KEV listing or active exploitation evidence. Exploitation requires local access, authenticated administrator privileges, high complexity, and user interaction, but successful exploitation may affect firmware trust boundaries.
Researcher notes
The source data names BIOSConnect but leaves versions unspecified. Avoid broad product claims without checking Dell advisory 000188682. The key technical concern is local admin-triggered memory corruption with potential arbitrary code execution and UEFI restriction bypass.
Mitigation direction
- Review Dell advisory 000188682 for affected systems and vendor remediation.
- Inventory Dell endpoints and identify BIOSConnect-capable systems.
- Prioritize remediation for systems with broad local administrator access.
- Reduce unnecessary local administrator rights where feasible.
- Track BIOS or firmware update status through normal change control.
Validation and detection
- Compare Dell model and BIOS versions against the Dell advisory.
- Confirm whether BIOSConnect is present on managed Dell systems.
- Review local administrator membership on in-scope endpoints.
- Verify remediation evidence in endpoint management or firmware inventory.
- Document unresolved systems with business owner and remediation date.
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-121: 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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-21573 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
- 7.2 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:C/C:H/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:H/PR:H/UI:R/S:C/C:H/I:H/A:H0.66Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.2HighVector: CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://www.dell.com/support/kbdoc/en-us/000188682CVE reference · x_refsource_MISC
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.
Stack-based Buffer Overflow
Stack-based Buffer Overflow represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.