Actively exploited vulnerability
Apple products: memory corruption flaw under attack
CVE-2021-30952 · Apple Multiple Products Integer Overflow or Wraparound Vulnerability
What is affected
Apple products are found on ordinary personal computers and phones, so this is not only a problem for companies. If you use them and have not updated since the fix was released, you are exposed.
Apple tvOS, macOS, Safari, iPadOS and watchOS contain an integer overflow or wraparound vulnerability due to the processing of maliciously crafted web content that may lead to arbitrary code execution.
What an attacker can do
This is a memory corruption flaw. It lets an attacker corrupt the program's memory by feeding it specially crafted content: a web page, a file or a network message. The result ranges from a crash to the attacker running their own code.
- How it is reached
- Needs access to the device or a file opened on it
- Access the attacker needs
- No account needed
- Does the victim have to do something?
- Yes, the victim must open or click something
What to do
- Update Apple products now. Open the update or "About" screen, install whatever is offered and restart the app or device, because the fix is not active until you do.
- Turn on automatic updates so the next fix arrives without you having to look for it.
- If your device is too old to receive this update, stop using the affected app for anything sensitive and plan a replacement.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Vendor advisories and fixes
- support.apple.comsupport.apple.com/en-us/HT212975
- support.apple.comsupport.apple.com/en-us/HT212976
- support.apple.comsupport.apple.com/en-us/HT212978
- support.apple.comsupport.apple.com/en-us/HT212980
- support.apple.comsupport.apple.com/en-us/HT212982
How urgent is it
CISA added this vulnerability to its Known Exploited Vulnerabilities catalogue on March 5, 2026, which means there is reliable evidence of attacks in the wild. US federal agencies must fix it by March 26, 2026, a deadline that has already passed. That deadline does not bind anyone else, but it shows how seriously the agency rates it.
The EPSS model estimates a 7.0% probability that this flaw will be exploited somewhere in the next 30 days. That is higher than 94% of all scored vulnerabilities.
Its CVSS severity score is 7.8 out of 10 (high), as recorded in the US National Vulnerability Database.
Technical description
An integer overflow was addressed with improved input validation. This issue is fixed in tvOS 15.2, macOS Monterey 12.1, Safari 15.2, iOS 15.2 and iPadOS 15.2, watchOS 8.3. Processing maliciously crafted web content may lead to arbitrary code execution.