What’s Vulnerable › Vulnerabilities

CVE-2021-1816

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-09-08 · updated 2026-06-17
• Weakness: CWE-119

Description

A buffer overflow was addressed with improved bounds checking. This issue is fixed in iOS 14.5 and iPadOS 14.5, watchOS 7.4, tvOS 14.5. A malicious application may be able to execute arbitrary code with kernel privileges.

Affected products

• Apple iPadOS: before 14.5 — fixed in 14.5
• Apple Iphone Os: before 14.5 — fixed in 14.5
• Apple tvOS: before 14.5 — fixed in 14.5
• Apple watchOS: before 7.4 — fixed in 7.4

How to fix

Upgrade to a fixed version: Apple iPadOS 14.5; Apple Iphone Os 14.5; Apple tvOS 14.5; Apple watchOS 7.4. Check the vendor advisory for mitigations.

References

• https://support.apple.com/en-us/HT212317
• https://support.apple.com/en-us/HT212323
• https://support.apple.com/en-us/HT212324
• https://support.apple.com/en-us/HT212317
• https://support.apple.com/en-us/HT212323
• https://support.apple.com/en-us/HT212324

Get alerted when CVE-2021-1816 or the next vulnerability affects your stack