CVE-2021-30665
Apple iOS, iPadOS, macOS, watchOS, and tvOS WebKit contain a memory corruption 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.
A memory corruption issue was addressed with improved state management. This issue is fixed in watchOS 7.4.1, iOS 14.5.1 and iPadOS 14.5.1, tvOS 14.6, iOS 12.5.3, macOS Big Sur 11.3.1. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H- support.apple.com/en-us/HT212335Release NotesVendor Advisory
- support.apple.com/en-us/HT212336Release NotesVendor Advisory
- support.apple.com/en-us/HT212339Release NotesVendor Advisory
- support.apple.com/en-us/HT212341Release NotesVendor Advisory
- support.apple.com/en-us/HT212532Release NotesVendor Advisory
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30665Third Party AdvisoryUS Government Resource
Actively exploited. Patch immediately.
- Exploitation
- Confirmed in the wild (CISA KEV)
- Federal remediation deadline
- Overdue by 1804 days
- CVSS
- 8.8 HIGH
- EPSS (30-day exploit probability)
- 3.7% · top 10% of all CVEs
- Weakness
- CWE-787
- Attack vector
- Network, remotely reachable
- 1.Apply updates per vendor instructions.
- 2.Treat as emergency change: patch or isolate internet-facing instances first.
- 3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
- 4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
Assessment is derived automatically from the live signals above; verify against your own asset inventory.