dbcve.org
SafariWeb browser · Apple

CVE-2018-4129

HIGH · 8.8 CVSS v3.0 Published 2018-04-03
Fix available
A fix is available. Upgrade to 2.20.4 / 4.3 or later.
See remediation →
95/100
Remediation priority · Urgent
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
An issue was discovered in certain Apple products. iOS before 11.3 is affected. Safari before 11.1 is affected. iCloud before 7.4 on Windows is affected. iTunes before 12.7.4 on Windows is affected. tvOS before 11.3 is affected. watchOS before 4.3 is affected. The issue involves the "WebKit" component. It allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted web site.

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 corruption vulnerability in WebKit allows remote attackers to execute arbitrary code or cause denial of service by tricking users into visiting a crafted malicious website. The vulnerability affects multiple Apple products including iOS, Safari, iCloud for Windows, iTunes for Windows, tvOS, and watchOS.

MitigationUpdate all affected Apple products to iOS 11.3+, Safari 11.1+, iCloud 7.4+, iTunes 12.7.4+, tvOS 11.3+, or watchOS 4.3+ respectively to patch the WebKit 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
SafariWeb browser
Affected:< 11.1
Ubuntu LinuxOperating system
Affected:= 16.04= 17.10
Iphone OsOperating system
Affected:< 11.3
TvosOperating system
Affected:< 11.3
WatchosOperating system
Affected:< 4.3
IcloudApplication
Affected:< 7.4
ItunesApplication
Affected:< 12.7.4
Webkitgtk\+Web browser
Affected:< 2.20.4

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
High
Integrity
High
Availability
High

CVSS:3.0/AV:N/AC:L/PR:N/UI:R/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. Identify WebKit-based applications installed
    List installed browsers and Apple applications: On macOS/Windows check for Safari, iTunes, iCloud. On Ubuntu check for packages containing webkitgtk. On iOS check Settings > General > About for iOS version.
    Affected if Any Safari, iTunes, iCloud, or WebKitGTK-based browser is installed on the system
  2. Check Safari version (macOS or Windows)
    Open Safari > Safari menu > About Safari. On Windows, open iTunes > Help > About iTunes. Note the version number displayed.
    Affected if Version is earlier than 11.1
  3. Check iOS version (iPhone/iPad)
    Open Settings > General > About on the iOS device. Note the Version number.
    Affected if Version is earlier than 11.3
  4. Check tvOS or watchOS version
    On Apple TV, go to Settings > General > About > Version. On Apple Watch, open the Watch app on iPhone > General > About.
    Affected if tvOS version is earlier than 11.3 or watchOS version is earlier than 4.3
  5. Check iTunes for Windows version
    Open iTunes > Help > About iTunes. Note the version number.
    Affected if Version is earlier than 12.7.4
  6. Check WebKitGTK version on Ubuntu
    Run command: dpkg -l | grep webkit or apt show libwebkit2gtk-4.0-37 (adjust package name as needed for your release).
    Affected if Version is earlier than 2.20.4

You are affected if any WebKit-based product (Safari, iTunes, iCloud, iOS, tvOS, watchOS, or WebKitGTK) is installed and its version falls below the minimum fixed version for that product.

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.

From vendor data
Upgrade available Upgrade to 2.20.4 / 4.3 / 7.4 or later
Fixed in 2.20.44.37.4
Interim mitigation

Update all affected Apple products to iOS 11.3+, Safari 11.1+, iCloud 7.4+, iTunes 12.7.4+, tvOS 11.3+, or watchOS 4.3+ respectively to patch the WebKit vulnerability.

Fix this in Safari Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing3.0 h
  • Review / QA2.0 h
17.0 hours of engineering $3,050
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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-2018-4129 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