Apple Multiple Products WebKit Memory Corruption Vulnerability

[ Why it matters ]Priority signals

• Exploited in the wild: on CISA's Known Exploited Vulnerabilities list since 2021-11-03

[ Description ]Official description

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..

CISA: 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.

[ Fixes ]Fixes and patches

CISA required action (US federal deadline 17 Nov 2021): Apply updates per vendor instructions.

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ References ]References

• 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
• www.cisa.gov/known-exploited-vulnerabilities-catalogThird Party AdvisoryUS Government Resource