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PatchSiren cyber security CVE debrief

CVE-2021-1789 Apple CVE debrief

CVE-2021-1789 is an Apple Multiple Products type confusion vulnerability that CISA listed in its Known Exploited Vulnerabilities catalog on 2022-05-04. The public records provided here do not include product-specific impact details, but the KEV listing is a strong signal to treat this as an active patch priority. CISA’s catalog entry set a remediation due date of 2022-05-25 and directs organizations to apply updates per vendor instructions.

Vendor
Apple
Product
Multiple Products
CVSS
Unknown
CISA KEV
Listed
Original CVE published
2022-05-04
Original CVE updated
2022-05-04
Advisory published
2022-05-04
Advisory updated
2022-05-04

Who should care

Apple device administrators, endpoint security teams, IT operations, and anyone responsible for updating managed macOS, iOS, iPadOS, watchOS, or other Apple platforms covered by vendor guidance should prioritize this CVE because it appears in CISA’s KEV catalog.

Technical summary

The supplied sources identify the issue as a type confusion vulnerability affecting multiple Apple products. Beyond that classification, the corpus does not provide the affected component, attack vector, or impact details. The key defensive fact is that CISA marked the vulnerability as known exploited and linked it to Apple remediation guidance.

Defensive priority

High. CISA KEV inclusion means defenders should treat this as an actively abused vulnerability and expedite patching across all relevant Apple fleets.

Recommended defensive actions

  • Apply Apple updates and security guidance for the affected products as soon as possible.
  • Confirm all managed Apple devices are on supported, fully patched versions.
  • Prioritize remediation for devices with broader exposure or weaker management coverage.
  • Validate patch completion through endpoint inventory and compliance reporting.
  • Monitor for vendor advisories or fleet exceptions that could leave some devices unpatched.

Evidence notes

The CVE record and NVD entry identify CVE-2021-1789 as an Apple Multiple Products vulnerability. CISA’s Known Exploited Vulnerabilities catalog lists it as a type confusion issue, added on 2022-05-04, with a remediation due date of 2022-05-25 and the required action 'Apply updates per vendor instructions.' The supplied corpus does not include additional technical specifics or a CVSS score.

Official resources

Public records in the supplied corpus identify the vulnerability on 2022-05-04, which is also the KEV date added. No exploit details are included here, and the debrief is limited to defensive, source-backed information.