CVE-2021-1879 Apple iOS, iPadOS, and watchOS WebKit Cross-Site Scripting (XSS)
Attackers can execute arbitrary scripts via malicious web content, potentially leading to code execution and security bypasses on Apple 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-2021-1879?
CVE-2021-1879 is a medium-severity cross-site scripting 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
This issue was addressed by improved management of object lifetimes. This issue is fixed in iOS 12.5.2, iOS 14.4.2 and iPadOS 14.4.2, watchOS 7.3.3. Processing maliciously crafted web content may lead to universal cross site scripting. Apple is aware of a report that this issue may have been actively exploited..
Weakness: CWE-79
Which versions are affected by CVE-2021-1879?
It affects 3 products.
Products include Apple Ipados, Apple Iphone Os, Apple Watchos.
How do I fix CVE-2021-1879?
No fix has been published for CVE-2021-1879 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 17 Nov 2021.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2021-1879 being exploited?
Yes. Attackers have exploited CVE-2021-1879 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-qhqp-qw35-f96r.