dbcve.org
SafariWeb browser · Apple

CVE-2021-30698

HIGH · 7.5 CVSS v3.1 Published 2021-09-08
Fix available
A fix is available. Upgrade to 11.4 / 14.1.1 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
A null pointer dereference was addressed with improved input validation. This issue is fixed in macOS Big Sur 11.4, Safari 14.1.1, iOS 14.6 and iPadOS 14.6. A remote attacker may be able to cause 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 · moderate confidence

A null pointer dereference vulnerability in WebKit (affecting Safari and Apple operating systems) that could be triggered by a remote attacker, leading to denial of service. The vulnerability was addressed through improved input validation.

MitigationUpdate affected systems to macOS Big Sur 11.4 or later, Safari 14.1.1 or later, iOS 14.6 or later, or iPadOS 14.6 or later.

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:< 14.1.1
IpadosOperating system
Affected:< 14.6
Iphone OsOperating system
Affected:< 14.6
macOSOperating system
Affected:>= 11.0, < 11.4

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
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 WebKit-based applications in use
    List all browsers or applications that use WebKit engine (Safari, embedded WebViews in apps). On macOS, check /Applications folder for Safari. On iOS/iPadOS, note any third-party browsers (which also use WebKit on iOS).
    Affected if Safari or any WebKit-based browser/app is actively used on the device
  2. Check installed macOS version
    On macOS, click Apple menu > About This Mac to view the version number (e.g., 11.3.1). Alternatively, run 'sw_vers -productVersion' in Terminal.
    Affected if macOS version is 11.0 through 11.3.x (any version >= 11.0 but < 11.4)
  3. Check installed Safari version
    On macOS, open Safari > Safari menu > About Safari to see the version (e.g., 14.1). On iOS/iPadOS, go to Settings > Safari > About to view the version.
    Affected if Safari version is below 14.1.1 (e.g., 14.0.x or earlier)
  4. Check iOS or iPadOS version
    On iPhone/iPad, go to Settings > General > About to view the iOS/iPadOS version number.
    Affected if iOS or iPadOS version is below 14.6 (e.g., 14.5.x or earlier)

You are affected if you run Safari, any WebKit-based browser, or WebKit-containing apps on macOS 11.0-11.3.x, iOS/iPadOS below 14.6, or Safari below 14.1.1.

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 11.4 / 14.1.1 / 14.6 or later
Fixed in 11.414.1.114.6
Interim mitigation

Update affected systems to macOS Big Sur 11.4 or later, Safari 14.1.1 or later, iOS 14.6 or later, or iPadOS 14.6 or later.

Recommended fix High confidence

macOS Big Sur 11.4, Safari 14.1.1, iOS 14.6, or iPadOS 14.6 depending on device

  1. For macOS: Open System Preferences > Software Update and install macOS Big Sur 11.4 or later
  2. For iOS: Go to Settings > General > Software Update and install iOS 14.6 or later
  3. For iPadOS: Go to Settings > General > Software Update and install iPadOS 14.6 or later
  4. For Safari: Update to Safari 14.1.1 by installing the corresponding macOS or iOS/iPadOS update
Caveat Standard Apple update risks apply - backup data before updating

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

Fix this in Safari Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA2.0 h
10.0 hours of engineering $1,780
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,848.

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-2021-30698 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