CVE-2020-9818 Apple iOS, iPadOS, and watchOS Out-of-Bounds Write
Attackers can execute arbitrary code or cause denial of service by sending a maliciously crafted mail message to Apple iOS devices.
- Exploited in the wild
- Since 3 Nov 2021
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2020-9818?
CVE-2020-9818 is a high-severity memory corruption vulnerability in Apple Ipados, published on 9 Jun 2020. 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
An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 13.5 and iPadOS 13.5, iOS 12.4.7, watchOS 6.2.5. Processing a maliciously crafted mail message may lead to unexpected memory modification or application termination.
Weakness: CWE-787
Which versions are affected by CVE-2020-9818?
It affects 3 products.
Products include Apple Ipados, Apple Iphone Os, Apple Watchos.
How do I fix CVE-2020-9818?
No fix has been published for CVE-2020-9818 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 3 May 2022.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2020-9818 being exploited?
Yes. Attackers have exploited CVE-2020-9818 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 GHSA-r647-89qj-xwmp.