CVE-2021-30840 Memory corruption in iOS and iPadOS
Processing a maliciously crafted dfont file may lead to arbitrary code execution on Apple operating systems.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2021-30840?
CVE-2021-30840 is a high-severity memory corruption vulnerability in Apple Ipados, published on 28 Oct 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
This issue was addressed with improved checks. This issue is fixed in tvOS 15, watchOS 8, iOS 15 and iPadOS 15. Processing a maliciously crafted dfont file may lead to arbitrary code execution.
Which versions are affected by CVE-2021-30840?
It affects 5 products.
Products include Apple Ipados, Apple Iphone Os, Apple Macos, Apple Tvos, Apple Watchos.
How do I fix CVE-2021-30840?
No fix has been published for CVE-2021-30840 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2021-30840 being exploited?
There is no known exploitation of CVE-2021-30840 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 GHSA-f3p9-xcq6-mf4q.