dbcve.org
IpadosOperating system · Apple

CVE-2024-40856

HIGH · 7.5 CVSS v3.1 Published 2024-09-17
Fix available
A fix is available. Upgrade to 15.0 / 18.0 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
An integrity issue was addressed with Beacon Protection. This issue is fixed in iOS 18 and iPadOS 18, macOS Sequoia 15, tvOS 18. An attacker may be able to force a device to disconnect from a secure network.

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 · high confidence

This is a vulnerability in Apple's Beacon Protection mechanism (used for network integrity) that allows an attacker to force a device to disconnect from a secure network. The vulnerability is an integrity issue that could be exploited to cause targeted devices to lose their secure network connection, potentially enabling man-in-the-middle attacks or denial of service.

MitigationApply the vendor-supplied updates: iOS 18 and later for iPhones/iPads, macOS Sequoia 15 and later for Macs, and tvOS 18 and later for Apple TV devices.

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
IpadosOperating system
Affected:< 18.0
Iphone OsOperating system
Affected:< 18.0
macOSOperating system
Affected:< 15.0

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
None
Integrity
None
Availability
High

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

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 Apple mobile devices in your environment
    Inventory iPhones and iPads using MDM solutions (Jamf, Microsoft Intune, etc.), Apple Configurator, or device enrollment programs. Check the iOS/iPadOS version on each device.
    Affected if iOS or iPadOS version is below 18.0
  2. Check iOS version on iPhones/iPads
    On each device: Settings > General > About. Or remotely via MDM: query the 'OSVersion' or 'ProductVersion' attribute. Compare against 18.0
    Affected if iOS or iPadOS version starts with a number lower than 18 (e.g., 17.x, 16.x, etc.)
  3. Identify Mac computers in your environment
    Inventory Mac systems using MDM (Jamf, Microsoft Intune), Active Directory, or local system enumeration. Check the macOS version on each Mac.
    Affected if macOS version is below 15.0
  4. Check macOS version on Mac computers
    On each Mac: Apple menu > About This Mac shows the version. Or use terminal: 'sw_vers -productVersion'. Remotely via MDM: query the 'OSVersion' attribute. Compare against 15.0
    Affected if macOS version starts with a number lower than 15 (e.g., 14.x, 13.x, etc.)
  5. Determine if Beacon Protection is in use
    Beacon Protection is a network integrity feature. Check if devices connect to networks that rely on this protection (typically enterprise or education networks using 802.1X with integrity checks). This is typically enabled by default on supported versions.
    Affected if Devices connect to networks relying on Beacon Protection integrity and are running versions below the fixed releases

A defender is affected if any Apple device (iPhone, iPad, or Mac) on their network runs iOS/iPadOS below 18.0 or macOS below 15.0, and those devices rely on Beacon Protection for network integrity.

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 15.0 / 18.0 or later
Fixed in 15.018.0
Interim mitigation

Apply the vendor-supplied updates: iOS 18 and later for iPhones/iPads, macOS Sequoia 15 and later for Macs, and tvOS 18 and later for Apple TV devices.

Recommended fix High confidence

iOS 18, iPadOS 18, macOS Sequoia 15

  1. For iOS/iPadOS devices: Back up your device using iCloud or Finder/iTunes, then go to Settings > General > Software Update and install iOS 18 or iPadOS 18
  2. For macOS devices: Back up your Mac using Time Machine, then go to System Settings > General > Software Update and install macOS Sequoia 15
  3. After upgrading, verify the update was successful by checking the OS version in Settings/About
Caveat Major OS upgrades may cause incompatibility with older applications; review app compatibility before upgrading

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

Fix this in Ipados Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,040
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,664.

Scan for this in your stack

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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-2024-40856 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