CVE-2021-30663 Apple Multiple Products WebKit Integer Overflow
Processing maliciously crafted web content may lead to arbitrary code execution due to an integer overflow in WebKit.
- Exploited in the wild
- Since 3 Nov 2021
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-30663?
CVE-2021-30663 is a high-severity vulnerability in Apple Ipados, published on 8 Sep 2021. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official 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.
Weakness: CWE-190
Which versions are affected by CVE-2021-30663?
It affects 5 products.
Products include Apple Ipados, Apple Iphone Os, Apple Macos, Apple Safari, Apple Tvos.
How do I fix CVE-2021-30663?
Upgrade to a fixed version. US federal agencies must fix it by 17 Nov 2021.
Is CVE-2021-30663 being exploited?
Yes. Attackers have exploited CVE-2021-30663 in the wild since at least 3 Nov 2021.
Other vulnerabilities in Apple Ipados
- CVE-2025-43300 Apple iOS, iPadOS, and macOS Out-of-Bounds Write
- CVE-2025-24201 Apple Multiple Products WebKit Out-of-Bounds Write
- CVE-2025-24085 Apple Multiple Products Use-After-Free
- CVE-2025-31200 Apple Multiple Products Memory Corruption
- CVE-2025-31201 Apple Multiple Products Arbitrary Read and Write
Sources
Also known as DEBIAN-CVE-2021-30663, GHSA-5g93-pf3w-6f59, UBUNTU-CVE-2021-30663.