What’s Vulnerable › Vulnerabilities
CVE-2021-1855
- Severity: medium (CVSS 6.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.8% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2021-09-08 · updated 2026-06-17
Description
A logic issue was addressed with improved state management. This issue is fixed in macOS Big Sur 11.3. A malicious website may be able to force unnecessary network connections to fetch its favicon.
Affected products
- Apple macOS: from 11.0 before 11.3 — fixed in 11.3
How to fix
Upgrade to a fixed version: Apple macOS 11.3. Check the vendor advisory for mitigations.
References
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