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IpadosOperating system · Apple

CVE-2021-30767

MEDIUM · 5.5 CVSS v3.1 Published 2021-12-23
Fix available
A fix is available. Upgrade to 10.15.7 / 11.6.2 or later.
See remediation →
57/100
Remediation priority · Elevated
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 logic issue was addressed with improved state management. This issue is fixed in macOS Big Sur 11.6.2, macOS Monterey 12.1, Security Update 2021-008 Catalina, iOS 15.2 and iPadOS 15.2, watchOS 8.3. A local user may be able to modify protected parts of the file system.

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

CVE-2021-30767 is a logic flaw in macOS/iOS state management that allows a local authenticated user to bypass file system protection mechanisms and modify protected parts of the file system. This constitutes a local privilege escalation vulnerability.

MitigationApply the relevant security updates: macOS Big Sur 11.6.2 or later, macOS Monterey 12.1 or later, Security Update 2021-008 for Catalina, iOS 15.2/iPadOS 15.2 or later, or watchOS 8.3 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
IpadosOperating system
Affected:< 15.2
Iphone OsOperating system
Affected:< 15.2
Mac Os XOperating system
Affected:>= 10.15, < 10.15.7= 10.15.7
macOSOperating system
Affected:>= 11.0, < 11.6.2>= 12.0, < 12.1
WatchosOperating system
Affected:<= 8.3

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
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

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 macOS version
    Run 'sw_vers -productVersion' in Terminal to get the exact version number (e.g., 11.5, 12.0, 10.15.7)
    Affected if The version is 10.15.x (10.15 to 10.15.7 inclusive), 11.0 to 11.6.1, or 12.0
  2. Identify iOS or iPadOS version
    On the device, go to Settings > General > About > Version to see the installed version
    Affected if The version is earlier than 15.2 (e.g., 15.1, 14.x, etc.)
  3. Identify watchOS version
    On Apple Watch, open the Settings app > General > About > Version, or pair with iPhone and check in the Watch app under General > About
    Affected if The version is 8.3 or earlier
  4. Verify System Integrity Protection status (macOS)
    Run 'csrutil status' in macOS Recovery or Terminal. If SIP is disabled, the system is more vulnerable to file system modification attacks
    Affected if SIP is disabled on an affected macOS version (10.15.x, 11.x, or 12.0)
  5. Check for local user accounts
    Run 'dscl . list /Users' to list local user accounts on macOS, or check Settings > Users & Groups on iOS/iPadOS
    Affected if Multiple local user accounts exist on an affected OS version, as the flaw allows any authenticated user to potentially escalate privileges

The environment is affected if the device runs any version of iOS/iPadOS before 15.2, watchOS 8.3 or earlier, or macOS versions 10.15.x, 11.0-11.6.1, or 12.0.

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 10.15.7 / 11.6.2 / 12.1 or later
Fixed in 10.15.711.6.212.1
Interim mitigation

Apply the relevant security updates: macOS Big Sur 11.6.2 or later, macOS Monterey 12.1 or later, Security Update 2021-008 for Catalina, iOS 15.2/iPadOS 15.2 or later, or watchOS 8.3 or later.

Recommended fix High confidence

iOS 15.2+, iPadOS 15.2+, macOS Big Sur 11.6.2+, macOS Monterey 12.1+, Security Update 2021-008 Catalina, watchOS 8.3+

  1. For iPhone/iPad: Go to Settings > General > Software Update and update to iOS/iPadOS 15.2 or later
  2. For macOS Catalina (10.15): Install Security Update 2021-008 Catalina through System Preferences > Software Update
  3. For macOS Big Sur (11.x): Update to macOS Big Sur 11.6.2 or later through System Preferences > Software Update
  4. For macOS Monterey (12.x): Update to macOS Monterey 12.1 or later through System Preferences > Software Update
  5. For Apple Watch: Update to watchOS 8.3 or later through the Watch app on iPhone
Caveat Standard OS update risks - ensure backups before updating

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

Fix this in Ipados Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,980
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,168.

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-2021-30767 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