What’s Vulnerable › Vulnerabilities

CVE-2021-30755

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.3% 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-125

Description

Processing a maliciously crafted font may result in the disclosure of process memory. This issue is fixed in macOS Big Sur 11.4, tvOS 14.6, watchOS 7.5. An out-of-bounds read was addressed with improved input validation.

Affected products

• Apple macOS: from 11.0 before 11.4 — fixed in 11.4
• Apple tvOS: before 14.6 — fixed in 14.6
• Apple watchOS: before 7.5 — fixed in 7.5

How to fix

Upgrade to a fixed version: Apple macOS 11.4; Apple tvOS 14.6; Apple watchOS 7.5. Check the vendor advisory for mitigations.

References

• https://support.apple.com/en-us/HT212529
• https://support.apple.com/en-us/HT212532
• https://support.apple.com/en-us/HT212533
• https://support.apple.com/en-us/HT212529
• https://support.apple.com/en-us/HT212532
• https://support.apple.com/en-us/HT212533

Get alerted when CVE-2021-30755 or the next vulnerability affects your stack