CVE-2025-43506Network attack vector

Private Relay failure via multiuser logic error

Published Dec 12, 2025 · Updated Dec 12, 2025

A logic error in the Networking component of Apple macOS before 26.1 causes iCloud Private Relay to fail during concurrent user logins. Apple identifies the locus only as Networking and has not published the affected routine or the erroneous operation performed during activation. The failure requires multiple logged-in users and can leave Safari browsing without Private Relay's IP-address and activity protections; no attacker-controlled trigger is documented.

CVSS severity7.5
High
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A logic error in the Networking component of Apple macOS before 26.1 causes iCloud Private Relay to fail during concurrent user logins. Apple identifies the locus only as Networking and has not published the affected routine or the erroneous operation performed during activation. The failure requires multiple logged-in users and can leave Safari browsing without Private Relay's IP-address and activity protections; no attacker-controlled trigger is documented.

The record

CVE
CVE-2025-43506
Published
Dec 12, 2025
Updated
Dec 12, 2025
Vendor
Apple
Product
macOS
Classifications
CWE-843
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 12, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 12, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <26.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Apple · macOSversion=unspecified <26.1

Published CVSS scores

7.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-843Access of Resource Using Incompatible Type ('Type Confusion')

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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