CVEvulnerability

CVE-2021-30663

8.8 HIGH Known exploited Published 2021-09-08 Modified 2026-06-17 Official page ↗

CISA Known Exploited Vulnerability

Apple Multiple Products WebKit Integer Overflow Vulnerability — Apple Multiple Products

Apple iOS, iPadOS, macOS, tvOS, and Safari WebKit contain an integer overflow 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.

Added to KEV
2021-11-03
Remediation due
2021-11-17
Ransomware use
Unknown
Required action
Apply updates per vendor instructions.
Notes
https://nvd.nist.gov/vuln/detail/CVE-2021-30663
Status
Analyzed
Published
2021-09-08
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
8.8 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS 3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
7.8 HIGH — CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS 2.0 ([email protected])
6.8 MEDIUM — AV:N/AC:M/Au:N/C:P/I:P/A:P
Weaknesses
CWE-190

Description

An integer overflow was addressed with improved input validation. This issue is fixed in iOS 14.5.1 and iPadOS 14.5.1, tvOS 14.6, iOS 12.5.3, Safari 14.1.1, macOS Big Sur 11.3.1. Processing maliciously crafted web content may lead to arbitrary code execution.

Affected configurations

• apple safari (< 14.1.1) • apple ipados (>= 14.0 < 14.5.1) • apple iphone os (< 12.5.3) • apple iphone os (>= 14.0 < 14.5.1) • apple macos (>= 11.0 < 11.3.1) • apple tvos (< 14.6)

Related

Weakness · CWE (1)

  • CWE-190 Integer Overflow or Wraparound weakness

Referenced by CWE · observed example (2)

  • CWE-190 Integer Overflow or Wraparound weakness
  • CWE-20 Improper Input Validation weakness

References