CVE-2021-1855

MEDIUM

6.5

CVSS Score

Published: September 8, 2021 at 02:45 PM UTC

Updated: June 17, 2026 at 03:32 AM UTC

1 product affected across 1 vendormacOS

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Severity

MEDIUM6.5

Exploit prediction

EPSS 0.8%

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

macOS · Apple

95%

v < 11.311.0 ≤ v < 11.3

Affected range stops below 11.3, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://support.apple.com/en-us/HT212325

References (1)

x_refsource_MISCVendor Advisory

Source: [email protected]

https://support.apple.com/en-us/HT212325

CVSS

6.5MEDIUM[email protected]

Attack Vector: NETWORK
Complexity: LOW
Privileges: NONE
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: LOW
Integrity: LOW
Availability: NONE

Vector?

Quick Info

StatusMODIFIED

CWE

NVD-CWE-noinfo

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