CISA KEV

CVE-2021-30858

Apple iOS, iPadOS, macOS Use-After-Free Vulnerability

Apple iOS, iPadOS, and macOS WebKit contain a use-after-free vulnerability that leads to code execution when processing maliciously crafted web content. This vulnerability could impact HTML parsers that use WebKit, including but not limited to Apple Safari and non-Apple products which rely on WebKit for HTML processing.

VendorApple

ProductiOS, iPadOS, and macOS

EPSS13.5%

Added to KEVNov 03, 2021

Remediation DueNov 17, 2021

Known Ransomware UseUnknown

CWECWE-416

Required Action

Apply updates per vendor instructions.

From Disclosure to Action

Know how quickly you need to move.

For CVE-2021-30858, added to the catalogue on Nov 03, 2021 with a remediation deadline of Nov 17, 2021.

Added to KEVNov 03, 2021

Seraph AlertSame day

Remediation DueNov 17, 2021

ValidationOngoing

Overdue1806 days overdue

Recommended action: Apply vendor remediation guidance.

Seraph Context

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Relevant Threat Actors

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Sector Context

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Exploitation Context

Campaign and indicator context, where Seraph analysts have published it.

References

https://nvd.nist.gov/vuln/detail/CVE-2021-30858

More from Apple in the KEV catalogue.

CVE-2026-65400macOSAdded Aug 18, 2026 CVE-2025-31277Multiple ProductsAdded Mar 20, 2026 CVE-2025-43520Multiple ProductsAdded Mar 20, 2026

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