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CVE Record

CVE-2021-33126: Improper access control in the firmware for some Intel(R) 700 and 722 Series Ethernet Controllers and Adapt...

Improper access control in the firmware for some Intel(R) 700 and 722 Series Ethernet Controllers and Adapters before versions 8.5 and 1.5.5 may allow a privileged user to potentially enable denial of service via local access.

MediumCVSS 4.4Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

This is an Intel Ethernet firmware access-control flaw. A user who already has high local privileges could potentially cause denial of service on systems using affected Intel 700 or 722 Series controllers or adapters. Business urgency is availability-focused, especially for servers or network-dependent workloads.

Executive priority

Treat this as a targeted availability risk. It is not described as remotely exploitable, but affected production servers should be patched during normal maintenance windows, with faster action for systems where network outage would disrupt critical services.

Technical view

CVE-2021-33126 affects firmware for some Intel 700 and 722 Series Ethernet Controllers and Adapters before versions 8.5 and 1.5.5. CVSS 3.1 is 4.4: local access, low complexity, high privileges, no user interaction, and high availability impact only.

Likely exposure

Exposure is limited to systems with affected Intel 700 or 722 Series Ethernet Controllers or Adapters running firmware before 8.5 or 1.5.5. The source bundle does not identify specific server models, operating systems, or cloud services.

Exploitation context

The bundle does not show CISA KEV listing or any cited evidence of active exploitation. The described attacker is a privileged local user, so this is mainly a post-access availability risk rather than an internet-facing initial compromise issue.

Researcher notes

The public details are sparse: no CWE is listed, and the bundle provides no exploit narrative beyond privileged local denial of service. Validate exposure through hardware and firmware inventory, then map the correct Intel advisory update to each affected platform.

Mitigation direction

  • Check Intel advisory INTEL-SA-00593 for the supported firmware update path.
  • Update affected firmware to version 8.5, 1.5.5, or later as applicable.
  • Prioritize systems where Ethernet adapter failure would affect production availability.
  • Restrict local privileged access on systems using affected adapters.
  • Monitor vendor guidance for platform-specific update packages.

Validation and detection

  • Inventory hosts using Intel 700 or 722 Series Ethernet Controllers or Adapters.
  • Record installed controller or adapter firmware versions.
  • Confirm whether firmware is before 8.5 or 1.5.5.
  • Verify remediation by rechecking firmware versions after update.
  • Review privileged local account access on affected systems.
Prepared
Confidence
high
Sources
3

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

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CVE-2021-33126 mapping review

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

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Vulnerability profileCVE Program record
Severity
Medium
CVSS
4.4 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/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
2Source 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
4.4CVSS 3.1MediumCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H0.83.6Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

4.4Medium
CVSS 3.1 vector shape for CVE-2021-33126Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/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) 700 and 722 Series Ethernet Controllers and Adaptersbefore versions 8.5 and 1.5.5Listed
Weakness

CWE details

No CWE listed

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