CVE-2021-1870Actively exploitedAdded to KEV 2021-11-03

Apple iOS, iPadOS, and macOS WebKit Remote Code Execution Vulnerability

Apple, iOS, iPadOS, and macOS

Description

Apple iOS, iPadOS, and macOS WebKit contain an unspecified logic vulnerability that allows a remote attacker to execute code. 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.

CVSS severity for this advisory hasn't been enriched from NVD yet, check back shortly.

EPSS, exploit probability

Medium

7.7%

estimated chance of real-world exploitation in the next 30 days, higher than 94.6% of every CVE FIRST.org scores

Refreshed 10/28/2026, via FIRST.org's EPSS model, not CVSS, this measures likelihood of exploitation, not how severe it would be.

Required action

Apply updates per vendor instructions.

CISA-recommended due date: 2021-11-17

CWE-1173

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