dbcve.org
IpadosOperating system · Apple

CVE-2023-40420

MEDIUM · 6.5 CVSS v3.1 Published 2023-09-27
Fix available
A fix is available. Upgrade to 10.0 / 12.7 or later.
See remediation →
72/100
Remediation priority · Elevated
Remotely reachable No privileges

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
The issue was addressed with improved memory handling. This issue is fixed in macOS Ventura 13.6, tvOS 17, iOS 16.7 and iPadOS 16.7, macOS Monterey 12.7, watchOS 10, iOS 17 and iPadOS 17, macOS Sonoma 14. Processing web content may lead to a denial-of-service.

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

A memory handling vulnerability in WebKit allows denial-of-service when processing malicious web content. The issue was addressed with improved memory handling, and patches have been released for macOS Ventura 13.6, Monterey 12.7, Sonoma 14, tvOS 17, watchOS 10, iOS 16.7/17, and iPadOS 16.7/17.

MitigationApply the available OS updates from Apple for the affected versions to remediate this vulnerability.

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:< 16.7
Iphone OsOperating system
Affected:< 16.7
macOSOperating system
Affected:>= 12.0.0, < 12.7>= 13.0, < 13.6
TvosOperating system
Affected:< 17.0
WatchosOperating system
Affected:< 10.0

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
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/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 the operating system
    Determine which Apple OS is running: iOS, iPadOS, macOS, tvOS, or watchOS. On iOS/iPadOS, go to Settings > General > About. On macOS, go to Apple menu > About This Mac. On tvOS/watchOS, go to Settings > General > About.
    Affected if The device runs any of the affected Apple operating systems.
  2. Check the installed iOS or iPadOS version
    On iOS/iPadOS, go to Settings > General > About and note the version number. Compare it against the affected range: versions earlier than 16.7 are vulnerable.
    Affected if iOS or iPadOS version is earlier than 16.7.
  3. Check the installed macOS version
    On macOS, go to Apple menu > About This Mac and note the version number. Compare against the affected ranges: 12.0.0 to before 12.7, or 13.0 to before 13.6.
    Affected if macOS version is 12.0.0 through 12.6.x, or 13.0 through 13.5.x.
  4. Check the installed tvOS version
    On Apple TV, go to Settings > General > About and note the version number. Versions earlier than 17.0 are affected.
    Affected if tvOS version is earlier than 17.0.
  5. Check the installed watchOS version
    On Apple Watch, go to Settings > General > About and note the version number. Versions earlier than 10.0 are affected.
    Affected if watchOS version is earlier than 10.0.
  6. Confirm WebKit is in use
    The vulnerability is triggered when processing malicious web content through WebKit. Any Apple browser (Safari, default browsers) uses WebKit. Verify that web browsing or web-based applications are accessible on the device.
    Affected if The device can render web content through WebKit-based browsers or embedded web views.

If the installed OS version falls below 16.7 for iOS/iPadOS, below 12.7 or between 13.0-13.5.x for macOS, below 17.0 for tvOS, or below 10.0 for watchOS, the device is vulnerable when processing malicious web content.

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 10.0 / 12.7 / 13.6 or later
Fixed in 10.012.713.6
Interim mitigation

Apply the available OS updates from Apple for the affected versions to remediate this vulnerability.

Recommended fix High confidence

iOS 16.7+/iPadOS 16.7+, macOS Monterey 12.7+, macOS Ventura 13.6+, tvOS 17+, watchOS 10+

  1. For iPhone/iPad users: Upgrade to iOS 16.7 or later (iOS 17 recommended for latest security)
  2. For iPad users: Upgrade to iPadOS 16.7 or later (iPadOS 17 recommended for latest security)
  3. For macOS Monterey (12.x) users: Upgrade to macOS Monterey 12.7
  4. For macOS Ventura (13.x) users: Upgrade to macOS Ventura 13.6
  5. For macOS Sonoma (14.x) users: Already fixed in initial release
  6. For tvOS users: Upgrade to tvOS 17 or later
  7. For watchOS users: Upgrade to watchOS 10 or later
Caveat Standard OS upgrade considerations apply - review app compatibility and backup data 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
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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-2023-40420 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