CVE-2021-1844 Memory corruption in macOS
Processing maliciously crafted web content in Safari may lead to arbitrary code execution due to a memory corruption issue.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-1844?
CVE-2021-1844 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 memory corruption issue was addressed with improved validation. This issue is fixed in iOS 14.4.1 and iPadOS 14.4.1, Safari 14.0.3 (v. 14610.4.3.1.7 and 15610.4.3.1.7), watchOS 7.3.2, macOS Big Sur 11.2.3. Processing maliciously crafted web content may lead to arbitrary code execution.
Weakness: CWE-787
Which versions are affected by CVE-2021-1844?
It affects 8 products.
Products include Apple Ipados, Apple Iphone Os, Apple Macos, Apple Safari, Apple Tvos, Apple Watchos and 2 more.
How do I fix CVE-2021-1844?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2021-1844 being exploited?
There is no known exploitation of CVE-2021-1844 in the wild and no public exploit code.
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-2021-1844, GHSA-7j8f-prmh-229c, UBUNTU-CVE-2021-1844.