LiveActive security incident?Get immediate response
CVE Record

CVE-2021-33103: Unintended intermediary in the BIOS authenticated code module for some Intel(R) Processors may allow a priv...

Unintended intermediary in the BIOS authenticated code module for some Intel(R) Processors may allow a privileged user to potentially enable aescalation of privilege via local access.

MediumCVSS 6.7Not KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

This is a firmware-level Intel processor issue where a user who already has high local privileges could potentially gain greater control. The business risk is mainly on systems where local administrators, service accounts, or compromised privileged users can reach affected Intel-based hardware.

Executive priority

Treat as a moderate firmware risk. It is not shown as actively exploited in the provided sources, but affected high-value infrastructure should be checked because successful abuse could have severe system-level impact.

Technical view

CVE-2021-33103 involves an unintended intermediary in the BIOS authenticated code module for some Intel processors. The CVSS vector is local, low complexity, high privileges required, no user interaction, with high confidentiality, integrity, and availability impact.

Likely exposure

Exposure is limited to systems using affected Intel processors and relevant BIOS or platform firmware. The provided bundle does not identify exact processor models; consult Intel SA-00601 and NetApp’s advisory for affected product mapping.

Exploitation context

The source bundle does not show CISA KEV listing or cited active exploitation. Exploitation requires local access and high privileges, so this is more concerning after endpoint compromise or insider misuse than as an initial remote entry point.

Researcher notes

Evidence is sparse in the provided bundle. The CVSS vector indicates post-compromise local privilege escalation with high privileges already required. Avoid assuming affected SKUs, exploit availability, or fixed versions without consulting Intel SA-00601 and downstream vendor advisories.

Mitigation direction

  • Review Intel SA-00601 for affected processor and firmware guidance.
  • Check OEM BIOS or platform firmware updates for affected hardware.
  • Review NetApp advisory if using NetApp products with Intel-based platforms.
  • Limit local administrative access on potentially affected systems.
  • Prioritize firmware maintenance for high-value servers and appliances.

Validation and detection

  • Inventory Intel processor models and BIOS firmware versions.
  • Compare assets against Intel SA-00601 affected product guidance.
  • Check NetApp advisory applicability for any NetApp appliances.
  • Confirm firmware remediation status through vendor management tooling.
  • Document systems where no vendor fix guidance is available.
Prepared
Confidence
medium
Sources
4

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

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 · low confidence lookup

CVE-2021-33103 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Medium
CVSS
6.7 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Official CVE source material

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.

1CVSS vectors
0Timeline events
0ADP providers
3Source links

CVSS vector scores

1 official score

We 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.

ScoreVersionSeverityVectorExploitImpactSource
6.7CVSS 3.1MediumCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H0.85.9Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

6.7Medium
CVSS 3.1 vector shape for CVE-2021-33103Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/aIntel(R) ProcessorsSee referencesListed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.