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CVE-2021-30900 Apple CVE debrief

CVE-2021-30900 is an Apple out-of-bounds write vulnerability affecting iOS, iPadOS, and macOS. CISA placed it in the Known Exploited Vulnerabilities catalog on 2023-03-30, indicating it has been observed as exploited in the wild and should be treated as a priority patching item. CISA’s due date for remediation was 2023-04-20.

Vendor
Apple
Product
iOS, iPadOS, and macOS
CVSS
Unknown
CISA KEV
Listed
Original CVE published
2023-03-30
Original CVE updated
2023-03-30
Advisory published
2023-03-30
Advisory updated
2023-03-30

Who should care

Apple platform administrators, mobile device management teams, endpoint security teams, and any organization that manages iPhones, iPads, or Macs should prioritize this CVE. Security teams responsible for KEV-driven remediation and compliance reporting should also track it closely.

Technical summary

The only technical detail available in the supplied corpus is that this Apple vulnerability is an out-of-bounds write affecting iOS, iPadOS, and macOS. The source corpus does not include the affected component, attack vector, or a vendor advisory write-up. Because CISA added the CVE to the KEV catalog, the practical takeaway is that the issue was known to be exploited and required prompt vendor-directed updating.

Defensive priority

High. KEV inclusion means this issue should be prioritized ahead of non-exploited vulnerabilities, especially on internet-facing, user-facing, or broadly deployed Apple devices.

Recommended defensive actions

  • Apply Apple updates per vendor instructions as soon as possible.
  • Use KEV-driven patch tracking to confirm all managed iOS, iPadOS, and macOS devices are remediated.
  • Validate remediation across mobile device management and endpoint inventory to catch off-network devices.
  • If full remediation is delayed, reduce exposure by limiting device access to sensitive services until updates are complete.
  • Monitor Apple and CISA sources for any advisory updates or follow-on guidance.

Evidence notes

Supported facts are limited to the supplied CVE metadata and CISA KEV entry. The corpus confirms the vulnerability type as an out-of-bounds write, the vendor as Apple, affected product families as iOS, iPadOS, and macOS, KEV publication on 2023-03-30, and remediation due date 2023-04-20. No CVSS score, exploit details, component name, or vendor advisory text was supplied.

Official resources

CISA added CVE-2021-30900 to the Known Exploited Vulnerabilities catalog on 2023-03-30 and set a remediation due date of 2023-04-20. The supplied corpus does not include the original vendor disclosure date.