Security readout for executives and security teams
Plain-English summary
CVE-2021-33137 is a high-severity local privilege escalation issue in Intel(R) Kernelflinger. An authenticated local user could potentially gain higher privileges. The provided sources do not identify active exploitation, and exact affected versions are not included in the bundle beyond Intel's advisory reference.
Executive priority
Treat this as a priority vulnerability where Intel(R) Kernelflinger is present, especially on systems with multiple local users. It is not supported as actively exploited by the provided sources, but successful abuse could compromise confidentiality, integrity, and availability.
Technical view
The flaw is an out-of-bounds write, classified as CWE-787, in Intel(R) Kernelflinger. CVSS 3.1 is 7.8: local attack vector, low complexity, low privileges required, no user interaction, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is limited to environments running affected Intel(R) Kernelflinger versions. The bundle does not list exact affected versions, so teams need to confirm applicability through Intel SA-00591 and internal asset or component inventory.
Exploitation context
The source bundle does not show CISA KEV listing or any cited evidence of active exploitation. Exploitation requires authenticated local access, which lowers internet-scale risk but remains serious on shared systems or where local accounts are broadly available.
Researcher notes
Evidence is sparse in the bundle: product is named, CWE and CVSS are provided, but affected version details are deferred to Intel's advisory. Do not assume exploit availability or affected downstream products without confirming against Intel SA-00591.
Mitigation direction
- Review Intel SA-00591 for affected versions and vendor guidance.
- Apply Intel-provided updates or mitigations if the advisory identifies them.
- Inventory systems or components using Intel(R) Kernelflinger.
- Restrict unnecessary local user access on potentially affected systems.
- Prioritize remediation where local users are untrusted or shared.
Validation and detection
- Check whether Intel(R) Kernelflinger exists in asset or component inventory.
- Compare deployed versions against Intel SA-00591 applicability details.
- Verify vendor-recommended updates or mitigations are applied.
- Confirm local account access is limited to authorized users.
- Document systems not affected and the evidence used.
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-787: 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-2021-33137 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
- 7.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/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:L/PR:L/UI:N/S:U/C:H/I:H/A:H1.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00591.htmlCVE 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.
Out-of-bounds Write
Out-of-bounds Write represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.