Security readout for executives and security teams
Plain-English summary
CVE-2021-30959 is an Apple macOS buffer overflow tied to audio file parsing. A malicious audio file could cause disclosure of user information. Apple says it fixed the issue with improved memory handling in Security Update 2021-008 Catalina and macOS Big Sur 11.6.2.
Executive priority
Treat this as a routine but real endpoint patching priority. The known impact is information disclosure, not code execution, and no active exploitation is cited. Systems that handle untrusted files should be updated promptly because the trigger is ordinary file parsing.
Technical view
The CVE describes a buffer overflow in macOS audio parsing, with the stated impact limited to user information disclosure. The public record does not provide CVSS, CWE, vulnerable component details, or version ranges beyond Apple macOS and the named fixed updates.
Likely exposure
Exposure is most relevant to macOS systems older than Security Update 2021-008 Catalina or macOS Big Sur 11.6.2, especially where users may open or preview untrusted audio files. The source bundle does not identify other Apple platforms or precise vulnerable builds.
Exploitation context
The provided sources do not state active exploitation, and the CVE is not marked KEV. The described attack condition is parsing a maliciously crafted audio file, but the public bundle provides no exploit maturity, delivery details, or in-the-wild evidence.
Researcher notes
Public detail is sparse: no CVSS, CWE, component path, or exact vulnerable version range is supplied. Analysis should stay anchored to Apple’s fixed-update statements and the CVE description. Do not assume broader platform impact or exploit availability from this bundle.
Mitigation direction
- Upgrade Catalina systems to Security Update 2021-008 or later vendor-supported guidance.
- Upgrade Big Sur systems to macOS Big Sur 11.6.2 or later vendor-supported guidance.
- Restrict handling of untrusted audio files on unpatched macOS systems.
- Prioritize patching shared workstations and high-risk user endpoints.
Validation and detection
- Inventory macOS systems and identify Catalina or Big Sur builds below the fixed updates.
- Confirm installed Apple security updates through endpoint management or asset inventory.
- Review whether affected users regularly receive or process untrusted audio files.
- Check Apple support pages for any superseding guidance or update availability.
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.
CVE-2021-30959 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/HT212979CVE reference · x_refsource_MISC
- https://support.apple.com/en-us/HT212981CVE 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.