CVE-2021-30859
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 · uneditedA type confusion issue was addressed with improved state handling. This issue is fixed in iOS 14.8 and iPadOS 14.8, macOS Big Sur 11.6, Security Update 2021-005 Catalina. A malicious 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 · high confidenceA type confusion vulnerability in Apple's kernel allowed a malicious application to execute arbitrary code with kernel privileges. The issue was addressed through improved state handling in the affected components.
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< 14.8< 14.8< 10.15.7= 10.15.7>= 11.0, < 11.6CVSS 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:3.1/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 checksWork through these to decide whether this CVE applies to you.
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Check iOS version on iPhoneGo to Settings > General > About and note the version number (e.g., 14.7.1)Affected if Version is less than 14.8 (e.g., 14.7, 14.6, etc.)
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Check iPadOS version on iPadGo to Settings > General > About and note the version numberAffected if Version is less than 14.8
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Check macOS versionClick Apple menu > About This Mac; the version is shown (e.g., 11.5, 10.15.6)Affected if Version is 10.15.7 or earlier, OR version is 11.0 through 11.5 (11.6 and later are fixed)
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Identify device model for iOS/iPadOSGo to Settings > General > About > Model Name to confirm iPhone or iPadAffected if Device runs iOS or iPadOS and version check from step 1 or 2 shows vulnerability
If the device runs iOS/iPadOS below 14.8, or macOS 10.15.7/earlier, or macOS Big Sur 11.0-11.5, the environment is affected by this kernel type confusion vulnerability.
Generated from the published advisory. Verify against your own configuration.
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 · scoped10.15.711.614.8
Apply the available security updates (iOS 14.8, iPadOS 14.8, macOS Big Sur 11.6, or Security Update 2021-005 Catalina) to all affected devices to prevent privilege escalation.
iOS 14.8 / iPadOS 14.8 / macOS Big Sur 11.6 / Security Update 2021-005 Catalina
- For iPhone and iPad: Go to Settings > General > Software Update and install iOS 14.8 or iPadOS 14.8
- For macOS Big Sur (11.x): Go to System Preferences > Software Update and install macOS Big Sur 11.6
- For macOS Catalina (10.15.7): Go to System Preferences > Software Update and install Security Update 2021-005 Catalina
- After updating, verify the installed version matches the fixed release in Settings/About
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,880.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-30859 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-30859 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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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.
- 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