dbcve.org
IpadosOperating system · Apple

CVE-2021-30889

HIGH · 8.8 CVSS v3.1 Published 2021-08-24
Fix available
A fix is available. Upgrade to 8.1 / 12.0.1 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
A buffer overflow issue was addressed with improved memory handling. This issue is fixed in macOS Monterey 12.0.1, iOS 15.1 and iPadOS 15.1, watchOS 8.1, tvOS 15.1. Processing maliciously crafted web content may lead to arbitrary code execution.

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 buffer overflow vulnerability in WebKit allows arbitrary code execution when processing maliciously crafted web content. The issue was addressed with improved memory handling in the affected Apple operating systems.

MitigationApply the security updates (iOS 15.1 and later, iPadOS 15.1 and later, watchOS 8.1 and later, tvOS 15.1 and later, macOS Monterey 12.0.1 and later) to all affected devices.

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:< 15.1
Iphone OsOperating system
Affected:< 15.1
macOSOperating system
Affected:< 12.0.1
TvosOperating system
Affected:< 15.1
WatchosOperating system
Affected:< 8.1

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
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/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 your Apple device type
    Determine whether the device is an iPhone, iPad, Mac, Apple Watch, or Apple TV. This matters because different OS version ranges apply to different device categories.
    Affected if Device is an iPhone, iPad, Mac, Apple Watch, or Apple TV running an affected OS version
  2. Check iOS or iPadOS version
    On iPhone or iPad, go to Settings > General > About. Note the version number displayed next to 'Version'. Compare it to 15.1 - any version below 15.1 is affected.
    Affected if iOS or iPadOS version is below 15.1
  3. Check macOS version
    On Mac, click the Apple menu > About This Mac. Note the version number (such as 12.0, 11.x, etc.). Compare it to 12.0.1 - any version below 12.0.1 is affected.
    Affected if macOS version is below 12.0.1
  4. Check watchOS version
    On Apple Watch, open the Settings app > General > About. Note the version. Or check via paired iPhone in Watch app > My Watch > About. Compare to 8.1 - any version below 8.1 is affected.
    Affected if watchOS version is below 8.1
  5. Check tvOS version
    On Apple TV, go to Settings > General > About TV. Note the version number. Compare to 15.1 - any version below 15.1 is affected.
    Affected if tvOS version is below 15.1
  6. Confirm WebKit is in use
    This vulnerability affects any app using WebKit on affected devices. Safari uses WebKit by default. Third-party browsers on iOS/iPadOS also use WebKit due to platform restrictions. Check if Safari or any WebKit-based browser is installed and used.
    Affected if Safari or any WebKit-based browser is used on a device with an affected OS version

A device is affected if it is an Apple device (iPhone, iPad, Mac, Apple Watch, or Apple TV) running an OS version below the fixed release (iOS/iPadOS/tvOS/watchOS 15.1 or macOS 12.0.1) and uses WebKit to render 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 8.1 / 12.0.1 / 15.1 or later
Fixed in 8.112.0.115.1
Interim mitigation

Apply the security updates (iOS 15.1 and later, iPadOS 15.1 and later, watchOS 8.1 and later, tvOS 15.1 and later, macOS Monterey 12.0.1 and later) to all affected devices.

Recommended fix High confidence

iOS 15.1+, iPadOS 15.1+, macOS Monterey 12.0.1+, watchOS 8.1+, tvOS 15.1+

  1. Identify the affected Apple device (iPhone, iPad, Mac, Apple Watch, or Apple TV)
  2. Determine the current installed OS version in Settings > General > About
  3. For iPhone/iPad: Go to Settings > General > Software Update and upgrade to iOS/iPadOS 15.1 or later
  4. For Mac: Go to System Preferences > Software Update and upgrade to macOS Monterey 12.0.1 or later
  5. For Apple Watch: Open the Watch app on iPhone, go to General > Software Update, and upgrade to watchOS 8.1 or later
  6. For Apple TV: Go to Settings > System > Software Updates and upgrade to tvOS 15.1 or later
  7. After upgrading, verify the new OS version is installed and confirm the vulnerability is patched
Caveat Major OS version upgrades may include feature changes; back up important data before upgrading

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

Fix this in Ipados Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
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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-2021-30889 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