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PatchSiren cyber security CVE debrief

CVE-2026-43727 Apple CVE debrief

A use-after-free issue was addressed with improved memory management in Apple Safari and other affected products. This issue could lead to an unexpected Safari crash when processing maliciously crafted web content. The vulnerability affects various Apple platforms, including Safari 26.5.2, iOS 26.5.2 and iPadOS 26.5.2, macOS Tahoe 26.5.2, visionOS 26.6, and watchOS 26.6. The issue requires user interaction (UI:R) and has a high impact on availability (A:H).

Vendor
Apple
Product
Safari
CVSS
MEDIUM 6.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-29
Original CVE updated
2026-07-27
Advisory published
2026-06-29
Advisory updated
2026-07-27

Who should care

Users of Apple products, particularly those using Safari, iOS, iPadOS, macOS, visionOS, and watchOS, should apply the latest security updates to prevent potential crashes from maliciously crafted web content. This includes administrators and security teams responsible for managing and securing Apple devices within their organizations.

Technical summary

The CVE-2026-43727 vulnerability involves a use-after-free issue in Apple Safari and other affected products. This issue could lead to an unexpected Safari crash when processing maliciously crafted web content. Apple has addressed this vulnerability through improved memory management in the specified security updates across various platforms. The vulnerability has a CVSS score of 6.5 and a severity rating of MEDIUM. It is crucial for organizations using affected Apple products to apply the latest security updates.

Defensive priority

Medium priority due to the potential for user interaction required (UI:R) and high impact on availability (A:H).

Recommended defensive actions

  • Apply the latest security updates for Safari, iOS, iPadOS, macOS, visionOS, and watchOS.
  • Ensure that web content is properly validated and sanitized before processing.
  • Implement compensating controls such as Content Security Policy (CSP) to restrict web content.
  • Monitor systems for unexpected Safari crashes or suspicious web activity.
  • Conduct regular inventory checks to ensure all Apple products are up-to-date.
  • Review relevant monitoring, detection, and logs for exposed assets that need extra review.
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented.

Evidence notes

The CVE record was published on 2026-06-29T20:17:37.133Z and was last modified on 2026-07-27T21:16:57.243Z. The NVD entry is currently Modified. This use-after-free issue affects multiple Apple products, including Safari, iOS, iPadOS, macOS, visionOS, and watchOS. Defenders should verify the affected products and versions in their environments, focusing on those with web content processing capabilities. The evidence is based on official CVE and NVD records, which may have limited detail.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-06-29T20:17:37.133Z and has not been modified since then. The NVD entry is currently Modified.