dbcve.org
SafariWeb browser · Apple

CVE-2025-43376

HIGH · 7.5 CVSS v3.1 Published 2025-11-04
Fix available
A fix is available. Upgrade to 26.0 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A logic issue was addressed with improved state management. This issue is fixed in Safari 26, iOS 18.7.7 and iPadOS 18.7.7, iOS 26 and iPadOS 26, macOS Tahoe 26, tvOS 26, visionOS 26, watchOS 26. A remote attacker may be able to view leaked DNS queries with Private Relay turned on.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

A logic error in Safari and Apple operating systems caused DNS queries to leak outside of the Private Relay tunnel, allowing a remote attacker with network access to potentially observe DNS queries that should have been encrypted and routed through Apple's Private Relay infrastructure.

MitigationUpdate to Safari 26, iOS/iPadOS 18.7.7 or later versions, macOS Tahoe 26, tvOS 26, visionOS 26, or watchOS 26 to receive the patch that corrects the state management logic.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
SafariWeb browser
Affected:< 26.0
IpadosOperating system
Affected:< 26.0
Iphone OsOperating system
Affected:< 26.0
VisionosOperating system
Affected:< 26.0
WatchosOperating system
Affected:< 26.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the Apple product and version
    On the device, go to Settings > General > About (iOS/iPadOS/watchOS/visionOS) or Safari > About Safari (macOS) to find the version number. For iPhone/iPad, check Settings app. For Apple Watch, use the Watch app on iPhone. For Vision Pro, check Settings > General > About.
    Affected if The installed version is Safari < 26.0, iOS < 26.0, iPadOS < 26.0, watchOS < 26.0, or visionOS < 26.0 (note: these correspond to iOS 18.7.6 and earlier, etc.)
  2. Verify Private Relay is enabled
    On iOS/iPadOS: go to Settings > [your name] > iCloud > Private Relay and check if it's turned on. On macOS: go to System Settings > [your name] > iCloud > Private Relay. On watchOS: use the Watch app on iPhone to check iCloud settings. On visionOS: check Settings > [your name] > iCloud > Private Relay.
    Affected if Private Relay is enabled and the version from step 1 is in the affected range below 26.0
  3. Confirm DNS leak exposure
    Use a network monitoring tool or visit a DNS leak test website (such as dnsleaktest.com) while connected to a network and with Private Relay enabled. Compare the DNS servers shown to Apple's Private Relay servers (typically 26.x.x.x or 27.x.x.x ranges).
    Affected if DNS queries resolve through non-Apple/DNS servers outside the expected Private Relay range, indicating queries are leaking outside the tunnel

You are affected if you are running Safari, iOS, iPadOS, watchOS, or visionOS version below 26.0 AND have Private Relay enabled, with DNS queries leaking to non-Private Relay servers.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 26.0 or later
Fixed in 26.0
Interim mitigation

Update to Safari 26, iOS/iPadOS 18.7.7 or later versions, macOS Tahoe 26, tvOS 26, visionOS 26, or watchOS 26 to receive the patch that corrects the state management logic.

Recommended fix High confidence

Safari 26.0, iOS 18.7.7/iOS 26, iPadOS 18.7.7/iPadOS 26, watchOS 26.0, visionOS 26.0, tvOS 26.0

  1. Upgrade Safari to version 26.0 or later
  2. Upgrade iPhone to iOS 18.7.7 (if on iOS 18.x) or iOS 26 (if on iOS 26)
  3. Upgrade iPad to iPadOS 18.7.7 (if on iPadOS 18.x) or iPadOS 26 (if on iPadOS 26)
  4. Upgrade Apple Watch to watchOS 26.0 or later
  5. Upgrade Apple Vision to visionOS 26.0 or later
  6. Upgrade Apple TV to tvOS 26.0 or later
  7. After updating, verify Private Relay is functioning correctly in Settings > Apple ID > iCloud > Private Relay
Caveat Users on older devices that cannot support iOS 18.7.7 or version 26 may not receive the security update; verify device compatibility before upgrading

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Safari Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
5.0 hours of engineering $890
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,424.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-43376 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data