What’s Vulnerable › Vulnerabilities
CVE-2020-9866
- Severity: critical (CVSS 9.8 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 1.9% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2020-10-27 · updated 2026-06-17
- Weakness: CWE-120
Description
A buffer overflow was addressed with improved bounds checking. This issue is fixed in macOS Catalina 10.15.6, Security Update 2020-004 Mojave, Security Update 2020-004 High Sierra. A buffer overflow may result in arbitrary code execution.
Affected products
- macOS: before 10.15.6 — fixed in 10.15.6
How to fix
Upgrade to a fixed version: macOS 10.15.6. Check the vendor advisory for mitigations.
References
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