Security readout for executives and security teams
Plain-English summary
Apple disclosed a macOS kernel vulnerability where a malicious app could gain kernel-level code execution. For executives, this means a compromised or untrusted app could reach the most privileged layer of a Mac. Apple says it fixed the issue in macOS Big Sur 11.6 and Security Update 2021-005 Catalina.
Executive priority
Treat this as a high-priority endpoint patching item because Apple identifies possible kernel-privileged code execution. Urgency is reduced only by the absence of source-provided active exploitation evidence.
Technical view
CVE-2021-30865 is an out-of-bounds read in macOS addressed by improved input validation. Apple’s impact statement says a malicious application may execute arbitrary code with kernel privileges. The source bundle does not provide CVSS, CWE, detailed affected version ranges, or exploit mechanics.
Likely exposure
Exposure is most likely on macOS systems older than Big Sur 11.6 or Catalina systems missing Security Update 2021-005. The sources list affected macOS versions as unspecified, so exact product and version boundaries are incomplete.
Exploitation context
The provided sources do not show CISA KEV listing or other evidence of active exploitation. The attack context described by Apple requires a malicious application and could result in kernel-privileged code execution.
Researcher notes
Public evidence is sparse. Apple names the bug class, impact, and fixed releases, but not root cause detail, exploitability conditions, CVSS, CWE, or precise vulnerable version ranges. Avoid assumptions beyond Apple’s advisory language.
Mitigation direction
- Update macOS Big Sur systems to 11.6 or later.
- Apply Security Update 2021-005 on macOS Catalina systems.
- Check Apple guidance for any version-specific update paths.
- Prioritize managed Macs that run third-party or internet-downloaded applications.
Validation and detection
- Inventory macOS versions across managed and unmanaged endpoints.
- Confirm Big Sur devices report version 11.6 or later.
- Confirm Catalina devices have Security Update 2021-005 installed.
- Check vulnerability management results for CVE-2021-30865 coverage.
- Review MDM compliance reports for failed or pending Apple security updates.
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.
Execution 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-2021-30865 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
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
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 and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://support.apple.com/en-us/HT212804CVE reference · x_refsource_MISC
- https://support.apple.com/en-us/HT212805CVE 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.