Security readout for executives and security teams
Plain-English summary
CVE-2021-30883 is an Apple memory corruption flaw that could let a malicious application run code with kernel-level control. Apple says it may have been actively exploited, and CISA lists it in KEV, so outdated Apple devices should be treated as urgent patch targets.
Executive priority
Treat this as a near-term remediation item. The business risk is elevated because successful exploitation reaches kernel privileges and exploitation is recognized by Apple and CISA KEV. Focus on rapid update compliance across Apple endpoints rather than extended analysis.
Technical view
The issue is a CWE-787 memory corruption vulnerability with local attack vector, low complexity, no privileges required, and user interaction required. Successful exploitation may allow arbitrary code execution with kernel privileges. Apple fixed it across iOS, iPadOS, macOS, tvOS, and watchOS releases listed in its advisories.
Likely exposure
Exposure is most likely on Apple devices running releases earlier than the fixed versions named by Apple: iOS/iPadOS 15.0.2 or 14.8.1, macOS Monterey 12.0.1, Big Sur 11.6.1, tvOS 15.1, and watchOS 8.1. Exact vulnerable version ranges are not provided in the bundle.
Exploitation context
Active exploitation is supported by Apple’s statement that it was aware of a report of exploitation and by CISA KEV listing. The sources do not provide exploit details, campaign attribution, or indicators of compromise.
Researcher notes
The bundle identifies fixed releases but not precise vulnerable version ranges, exploit mechanics, or indicators. Validation should center on OS build inventory and patch status. Avoid assuming exposure outside Apple products listed by the advisories.
Mitigation direction
- Update affected Apple devices to the fixed releases or later.
- Prioritize managed mobile devices, executive devices, and developer workstations.
- Check Apple advisories for product-specific update guidance.
- Remove or isolate devices that cannot receive supported security updates.
- Review mobile device management compliance for outdated OS versions.
Validation and detection
- Inventory Apple devices and record OS versions.
- Confirm devices meet or exceed Apple’s fixed release versions.
- Check MDM reports for noncompliant or unmanaged endpoints.
- Review EDR/MDM telemetry for suspicious application execution where available.
- Document exceptions for unsupported devices and compensating controls.
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-2021-30883 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/HT212869CVE reference · x_refsource_MISC
- https://support.apple.com/en-us/HT212872CVE reference · x_refsource_MISC
- https://support.apple.com/en-us/HT212846CVE reference · x_refsource_MISC
- https://support.apple.com/en-us/HT212868CVE reference · x_refsource_MISC
- https://support.apple.com/en-us/HT212874CVE reference · x_refsource_MISC
- https://support.apple.com/en-us/HT212876CVE reference · x_refsource_MISC
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30883CVE 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.