Security readout for executives and security teams
Plain-English summary
This issue affects some Intel Ethernet adapter and I225 manageability firmware. A person who already has high local privileges could potentially raise privileges by abusing improper neutralization in firmware. It is not a remote, unauthenticated internet attack based on the provided sources.
Executive priority
Prioritize remediation for servers, workstations, and appliances where privileged local compromise would disrupt operations. This is not presented as internet-exploited, but firmware-level privilege escalation can increase impact after an attacker already has local privileged access.
Technical view
CVE-2021-33158 is CWE-86 in Intel Ethernet Adapters and Intel Ethernet Controller I225 Manageability firmware. CVSS 3.1 is 7.2 with local attack vector, high complexity, high privileges required, no user interaction, changed scope, and high integrity and availability impact.
Likely exposure
Exposure is likely limited to systems using the affected Intel Ethernet adapters or Intel Ethernet Controller I225 manageability firmware versions listed by Intel SA-00756. The bundle does not include exact affected versions.
Exploitation context
The source bundle does not show active exploitation, and KEV is false. Exploitation requires local access by a privileged user and has high attack complexity, reducing broad exploitation likelihood but still creating insider or post-compromise risk.
Researcher notes
Do not infer affected versions or fixes beyond Intel SA-00756. The provided CVE data names the product family and CVSS vector, but exact firmware ranges and remediation specifics must come from Intel or OEM guidance.
Mitigation direction
- Review Intel SA-00756 for affected adapter and firmware version details.
- Apply Intel or OEM firmware updates if the advisory lists them.
- Restrict local administrative access to affected systems.
- Track OEM platform advisories for bundled network firmware updates.
- Document compensating controls where firmware updates are unavailable.
Validation and detection
- Inventory Intel Ethernet adapter models and I225 controllers in managed assets.
- Compare installed manageability firmware versions with Intel SA-00756.
- Confirm whether affected systems allow unnecessary local privileged access.
- Verify applied firmware or OEM update levels after remediation.
- Record systems requiring vendor guidance or deferred remediation.
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-86: 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-2021-33158 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:N/S:C/C:N/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:N/S:C/C:N/I:H/A:H0.85.8Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.2HighVector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:N/I:H/A:H
Source materials
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.
Improper Neutralization of Invalid Characters in Identifiers in Web Pages
Improper Neutralization of Invalid Characters in Identifiers in Web Pages represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.