CVE-2021-30809 Use after free in Safari
Processing maliciously crafted web content in Safari may lead to arbitrary code execution due to a use-after-free vulnerability.
- 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-2021-30809?
CVE-2021-30809 is a high-severity use after free vulnerability in Apple Ipados, published on 28 Oct 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 use after free issue was addressed with improved memory management. This issue is fixed in Safari 15, tvOS 15, watchOS 8, iOS 15 and iPadOS 15. Processing maliciously crafted web content may lead to arbitrary code execution.
Weakness: CWE-416
Which versions are affected by CVE-2021-30809?
It affects 6 products.
Products include Apple Ipados, Apple Iphone Os, Apple Macos, Apple Safari, Apple Tvos, Apple Watchos.
How do I fix CVE-2021-30809?
Upgrade to a fixed version.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2021-30809 being exploited?
There is no known exploitation of CVE-2021-30809 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
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-2021-30809, GHSA-6gcj-5f9m-97rp, UBUNTU-CVE-2021-30809.