Security readout for executives and security teams
Plain-English summary
This Apple vulnerability could let a malicious application gain kernel-level control on affected devices. Apple fixed it in macOS Big Sur 11.5.1, iOS/iPadOS 14.7.1, and watchOS 7.6.1. Because Apple reported possible exploitation and CISA lists it as known exploited, outdated Apple endpoints deserve urgent attention.
Executive priority
Treat as urgent patching for Apple endpoints because exploitation is supported by Apple reporting and CISA KEV. The practical business risk is device compromise with kernel privileges on unpatched systems.
Technical view
CVE-2021-30807 is a CWE-787 memory corruption issue addressed by improved memory handling. The published impact is arbitrary code execution with kernel privileges by an application. CVSS 3.1 is 7.8: local attack vector, low complexity, no privileges, user interaction required, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is most likely on Apple devices not updated to macOS Big Sur 11.5.1, iOS/iPadOS 14.7.1, watchOS 7.6.1, or later applicable fixes. The provided sources do not give complete vulnerable version ranges or device model boundaries.
Exploitation context
Apple stated it was aware of a report that the issue may have been actively exploited. CISA KEV listing supports treating this as known exploited. The CVSS vector indicates local execution with user interaction, but the sources do not provide exploit details or indicators.
Researcher notes
The bundle identifies a memory corruption vulnerability with kernel privilege impact and CVSS 7.8. It does not provide root cause detail, indicators, affected build ranges beyond fixed versions, or exploit mechanics. Avoid assuming product scope beyond Apple’s referenced updates.
Mitigation direction
- Update affected Apple devices to the fixed versions or later supported releases.
- Prioritize remediation for internet-facing staff devices, executives, and high-value users.
- Use MDM or endpoint management to enforce minimum Apple OS versions.
- Check Apple security guidance for any later superseding updates.
- Remove or isolate devices that cannot be updated promptly.
Validation and detection
- Inventory macOS, iOS, iPadOS, and watchOS versions across managed assets.
- Confirm macOS Big Sur 11.5.1 or later where applicable.
- Confirm iOS and iPadOS 14.7.1 or later where applicable.
- Confirm watchOS 7.6.1 or later where applicable.
- Review endpoint telemetry for suspicious untrusted application execution where available.
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 lookupExecution 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-2021-30807 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
- Yes
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/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.
CISA KEV status
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:N/UI:R/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:N/UI:R/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://support.apple.com/en-us/HT212622CVE reference · x_refsource_MISC
- https://support.apple.com/en-us/HT212623CVE reference · x_refsource_MISC
- https://support.apple.com/en-us/HT212713CVE reference · x_refsource_MISC
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30807CVE reference · government-resource
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.