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IpadosOperating system · Apple

CVE-2021-1851

HIGH · 8.8 CVSS v3.1 Published 2021-09-08
Fix available
A fix is available. Upgrade to 7.4 / 11.3 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
A logic issue was addressed with improved state management. This issue is fixed in Security Update 2021-002 Catalina, Security Update 2021-003 Mojave, iOS 14.5 and iPadOS 14.5, watchOS 7.4, tvOS 14.5, macOS Big Sur 11.3. An application may be able to execute arbitrary code with kernel privileges.

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 logic error in state management within Apple operating systems allows a malicious application to escalate privileges to kernel level, enabling arbitrary code execution with the highest system privileges. This is a local privilege escalation vulnerability requiring the attacker to first execute code on the target system.

MitigationApply the relevant Apple security updates (2021-002 for Catalina, 2021-003 for Mojave, iOS/iPadOS 14.5, watchOS 7.4, tvOS 14.5, or macOS Big Sur 11.3) to all affected devices. Prioritize endpoints based on exposure and criticality.

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:< 14.5
Iphone OsOperating system
Affected:< 14.5
Mac Os XOperating system
Affected:= 10.14= 10.14.0= 10.14.1= 10.14.2= 10.14.3= 10.14.4= 10.14.5= 10.14.6= 10.15= 10.15.1= 10.15.2= 10.15.3
macOSOperating system
Affected:>= 11.0, < 11.3
TvosOperating system
Affected:< 14.5
WatchosOperating system
Affected:< 7.4

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:3.1/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 the operating system type
    Determine if the device is running iOS, iPadOS, macOS, tvOS, or watchOS. On macOS, run 'sw_vers' in Terminal. On iOS/iPadOS, go to Settings > General > About. On tvOS/watchOS, check in Settings > General > About.
    Affected if The device runs any of the affected Apple operating systems (iOS, iPadOS, macOS, tvOS, watchOS)
  2. Check iOS or iPadOS version
    Go to Settings > General > About on the iOS/iPadOS device and note the version number (e.g., 14.4, 14.4.1).
    Affected if The installed version is lower than 14.5 (such as 14.0 through 14.4.x)
  3. Check macOS version
    Run 'sw_vers' in Terminal or go to Apple menu > About This Mac to view the macOS version (e.g., 10.14.6, 10.15.7, 11.2).
    Affected if The version is 10.14.x, 10.15.x, or 11.0-11.2.x (specifically 10.14 through 10.14.6, 10.15 through 10.15.3, or 11.0 through 11.2.x)
  4. Verify exact macOS Sierra version
    Run 'sw_vers -productVersion' to get the precise version (e.g., 10.14.6). Compare against the affected list: 10.14, 10.14.0, 10.14.1, 10.14.2, 10.14.3, 10.14.4, 10.14.5, 10.14.6.
    Affected if The macOS version exactly matches 10.14, 10.14.0, 10.14.1, 10.14.2, 10.14.3, 10.14.4, 10.14.5, or 10.14.6
  5. Verify exact macOS Catalina version
    Run 'sw_vers -productVersion' to get the precise version. Compare against the affected list: 10.15, 10.15.1, 10.15.2, 10.15.3.
    Affected if The macOS version exactly matches 10.15, 10.15.1, 10.15.2, or 10.15.3
  6. Check tvOS or watchOS version
    On tvOS, go to Settings > General > About > Version. On watchOS, open the Watch app on iPhone > General > About > watchOS Version.
    Affected if The tvOS version is lower than 14.5 or watchOS version is lower than 7.4

The device is affected if it runs iOS/iPadOS, tvOS, or watchOS versions below 14.5, 7.4 respectively, or macOS versions 10.14.x, 10.15.x, or 11.0-11.2.x.

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 7.4 / 11.3 / 14.5 or later
Fixed in 7.411.314.5
Interim mitigation

Apply the relevant Apple security updates (2021-002 for Catalina, 2021-003 for Mojave, iOS/iPadOS 14.5, watchOS 7.4, tvOS 14.5, or macOS Big Sur 11.3) to all affected devices. Prioritize endpoints based on exposure and criticality.

Recommended fix High confidence

iOS 14.5+, iPadOS 14.5+, macOS 11.3+, Security Update 2021-002/2021-003, watchOS 7.4+, tvOS 14.5+

  1. For iOS devices: Go to Settings > General > Software Update and upgrade to iOS 14.5 or later
  2. For iPadOS devices: Go to Settings > General > Software Update and upgrade to iPadOS 14.5 or later
  3. For macOS Big Sur (11.x): Go to System Preferences > Software Update and upgrade to macOS 11.3 or later
  4. For macOS Catalina (10.14.x): Apply Security Update 2021-002 from Apple menu > System Preferences > Software Update
  5. For macOS Mojave (10.14.x): Apply Security Update 2021-003 from Apple menu > System Preferences > Software Update
  6. For Apple Watch: Open the Watch app on iPhone, go to General > Software Update and upgrade to watchOS 7.4 or later
  7. For Apple TV: Go to Settings > System > Software Updates and upgrade to tvOS 14.5 or later
Caveat Standard OS update; review release notes for any behavioral changes

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

Fix this in Ipados Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing8.0 h
  • Review / QA4.0 h
36.0 hours of engineering $6,400
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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-2021-1851 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