Iphone OsOperating system · Apple

CVE-2018-4367

CRITICAL · 9.8 CVSS v3.0 Published 2019-04-03
Fix available
A fix is available. Upgrade to 12.1 or later.
See remediation →
100/100
Remediation priority · Urgent
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 memory corruption issue was addressed with improved input validation. This issue affected versions prior to iOS 12.1.

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 memory corruption vulnerability in iOS WebKit components that was exploitable via malicious web content. The fix involved improved input validation to prevent the memory corruption that could allow arbitrary code execution.

MitigationUpdate affected iOS devices to version 12.1 or later to apply Apple's patch. This is a remote code execution vulnerability exploitable through Safari/web content.

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
Iphone OsOperating system
Affected:< 12.1

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
High
Availability
High

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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. Check iOS version installed on the device
    Go to Settings > General > About and look at the Version field. Alternatively, connect to a computer with iTunes or Finder and check the device summary page.
    Affected if The version displayed is lower than 12.1 (for example, 12.0.x, 11.x, or earlier)
  2. Identify if WebKit-based browsers or apps are used
    On iOS, Safari and many third-party browsers use the WebKit rendering engine. Check if any browser or app that renders web content is in use.
    Affected if Any WebKit-based browser or app is used on an iOS device running a version below 12.1
  3. Confirm exposure to untrusted web content
    Determine whether the device has accessed or could access websites other than trusted, known-good sources, particularly through Safari or other WebKit-based applications.
    Affected if The device can browse the web or load web content from arbitrary sources on an iOS version below 12.1

The device is affected if it runs iOS versions earlier than 12.1 and uses WebKit-based applications to access 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 12.1 or later
Fixed in 12.1
Interim mitigation

Update affected iOS devices to version 12.1 or later to apply Apple's patch. This is a remote code execution vulnerability exploitable through Safari/web content.

Recommended fix High confidence

iOS 12.1 or later

  1. Back up your iOS device data to preserve important information
  2. Connect your device to a power source and ensure stable Wi-Fi connectivity
  3. Navigate to Settings > General > Software Update on the device
  4. Download and install iOS 12.1 or later version
  5. Verify the update was successful by checking Settings > General > About > Version
Caveat Upgrading iOS may introduce compatibility issues with older applications or accessories; review app compatibility before upgrading

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

Fix this in Iphone Os Scoped from the published advisory
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing1.0 h
  • Review / QA1.0 h
5.0 hours of engineering $910
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,456.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2018-4367 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

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-2018-4367 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