Security readout for executives and security teams
Plain-English summary
Dell BIOSConnect has a buffer overflow that could let a local authenticated administrator run code outside normal UEFI restrictions. This is serious, but the CVE requires local admin privileges, high attack complexity, and user interaction, reducing broad remote exposure.
Executive priority
Treat as a high-priority endpoint firmware issue, especially for privileged laptops or workstations. Broad emergency response is not supported by the provided evidence, but unvalidated Dell fleets should be assessed promptly.
Technical view
CVE-2021-21574 is a CWE-121 stack-based buffer overflow in Dell BIOSConnect. The CVSS 3.1 score is 7.2 with local attack vector, high complexity, high privileges, user interaction, scope change, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is limited to Dell systems using BIOSConnect. The source bundle does not identify specific Dell models, BIOS versions, or affected release ranges, so asset validation must be based on Dell’s advisory and local inventory.
Exploitation context
The bundle does not show CISA KEV listing or other evidence of active exploitation. Exploitation requires an authenticated malicious admin with local access and user interaction, but successful abuse could bypass UEFI restrictions.
Researcher notes
The CVE record provides impact and prerequisites but not affected model or version granularity in the supplied bundle. Avoid assuming exploitability beyond local authenticated admin context and validate details against Dell’s advisory.
Mitigation direction
- Review Dell advisory 000188682 for affected models and supported remediation.
- Apply Dell-provided BIOS or BIOSConnect guidance where applicable.
- Restrict local administrator access on Dell endpoints.
- Prioritize systems used for privileged administration or sensitive workloads.
- Monitor Dell support channels for model-specific updates.
Validation and detection
- Inventory Dell systems where BIOSConnect is present or enabled.
- Compare each system against Dell advisory 000188682.
- Check BIOS or firmware status through approved endpoint management tooling.
- Review local administrator membership for affected systems.
- Confirm remediation status in vulnerability management records.
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-2021-21574 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.