Iphone OsOperating system · Apple

CVE-2018-4303

HIGH · 7.8 CVSS v3.0 Published 2019-04-03
Fix available
A fix is available. Upgrade to 5.1.2 / 10.14 or later.
See remediation →
81/100
Remediation priority · High
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 input validation issue was addressed with improved input validation. This issue affected versions prior to macOS Mojave 10.14, iOS 12.1.1, macOS Mojave 10.14.2, tvOS 12.1.1, watchOS 5.1.2.

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

An input validation vulnerability in multiple Apple operating systems (macOS, iOS, tvOS, watchOS) allowed potentially malicious input to be processed improperly. The issue was addressed through improved input validation mechanisms in the patched versions.

MitigationUpdate affected devices to macOS Mojave 10.14.2, iOS 12.1.1, tvOS 12.1.1, or watchOS 5.1.2 or later 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
Iphone OsOperating system
Affected:< 12.1.1
Mac Os XOperating system
Affected:< 10.14= 10.14.1
TvosOperating system
Affected:< 12.1.1
WatchosOperating system
Affected:< 5.1.2

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
Local
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.0/AV:L/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. Check iOS version on iPhone or iPad
    Go to Settings > General > About and look at the 'Version' field, or run 'nsurlcache -v' or check via Apple Configurator or MDM
    Affected if The version is lower than 12.1.1 (e.g., 12.0, 12.0.1, 12.1)
  2. Check macOS version on Mac
    Click the Apple menu > About This Mac, or run 'sw_vers' in Terminal
    Affected if The version is 10.14.0 or 10.14.1 specifically (10.14.0 is < 10.14, and 10.14.1 equals 10.14.1 in the affected range)
  3. Check tvOS version on Apple TV
    Go to Settings > General > About > Version, or check via Apple Configurator or MDM
    Affected if The version is lower than 12.1.1 (e.g., 12.0, 12.0.1, 12.1)
  4. Check watchOS version on Apple Watch
    Open the Watch app on iPhone, go to My Watch > General > About, or check via Apple Configurator
    Affected if The version is lower than 5.1.2 (e.g., 5.0, 5.1, 5.1.1)

A user is affected if their device runs iOS, tvOS, or watchOS versions before 12.1.1/5.1.2, or macOS 10.14 or 10.14.1, since the input validation fix was applied in the subsequent point releases.

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 5.1.2 / 10.14 / 12.1.1 or later
Fixed in 5.1.210.1412.1.1
Interim mitigation

Update affected devices to macOS Mojave 10.14.2, iOS 12.1.1, tvOS 12.1.1, or watchOS 5.1.2 or later to remediate this vulnerability.

Fix this in Iphone Os Scoped from the published advisory
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,060
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Scan for this in your stack

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dbcve dependency scanner

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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-2018-4303 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