CVE-2021-1789 Apple Multiple Products Type Confusion
Attackers can execute arbitrary code by tricking users into visiting malicious web content in Safari or other WebKit-based apps on Apple devices.
- Exploited in the wild
- Since 4 May 2022
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-1789?
CVE-2021-1789 is a high-severity memory corruption vulnerability in Apple Ipados, published on 2 Apr 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
A type confusion issue was addressed with improved state handling. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, tvOS 14.4, watchOS 7.3, iOS 14.4 and iPadOS 14.4, Safari 14.0.3. Processing maliciously crafted web content may lead to arbitrary code execution.
Weakness: CWE-843
Which versions are affected by CVE-2021-1789?
It affects 8 products.
Products include Apple Ipados, Apple Iphone Os, Apple Mac Os X, Apple Macos, Apple Tvos, Apple Watchos and 2 more.
How do I fix CVE-2021-1789?
Upgrade to a fixed version. US federal agencies must fix it by 25 May 2022.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2021-1789 being exploited?
Yes. Attackers have exploited CVE-2021-1789 in the wild since at least 4 May 2022.
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-2021-1789, GHSA-c838-pj7m-89q4, UBUNTU-CVE-2021-1789.