dbcve.org
Actively exploited in the wild. This CVE is on the CISA Known Exploited Vulnerabilities list — treat remediation as urgent. Federal remediation due by 20 Apr 2023.
IpadosOperating system · Apple

CVE-2021-30900

HIGH · 7.8 CVSS v3.1 Published 2021-08-24
Fix available
A fix is available. Upgrade to 11.6.1 / 14.8.1 or later.
See remediation →
97/100
Remediation priority · Urgent
In the wild 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
An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 14.8.1 and iPadOS 14.8.1, iOS 15.1 and iPadOS 15.1. 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 · moderate confidence

An out-of-bounds write vulnerability in iOS and iPadOS that allows a malicious application to execute arbitrary code with kernel privileges. The issue was addressed with improved bounds checking and affects iOS versions prior to 14.8.1 and 15.1.

MitigationUpdate affected iOS/iPadOS devices to version 14.8.1 or later (or 15.1+) to apply the bounds checking fix.

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:< 14.8.1= 15.0
Iphone OsOperating system
Affected:< 14.8.1= 15.0
macOSOperating system
Affected:< 11.6.1

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
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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify the device type and operating system
    Determine if the device is an iPhone, iPad, or Mac. For iOS/iPadOS, go to Settings > General > About. For macOS, check System Preferences > About or run 'sw_vers' in Terminal.
    Affected if Device runs iOS, iPadOS, or macOS
  2. Check iOS/iPadOS version on iPhone or iPad
    On the device, go to Settings > General > About and note the Version number (for example, 15.0, 14.8, 13.7).
    Affected if Version is less than 14.8.1 or exactly equals 15.0
  3. Check macOS version on Mac
    Open System Preferences > About or run the command 'sw_vers' in Terminal and note the OS version (for example, 11.6, 12.0, 10.15).
    Affected if Version is less than 11.6.1 (this includes 11.0 through 11.6.0)
  4. Confirm kernel-level exposure
    This vulnerability is a kernel flaw that can be exploited by any malicious application. No specific kernel extension, configuration, or feature needs to be enabled for the device to be vulnerable.
    Affected if The device runs any affected iOS/iPadOS or macOS version listed above

The device is affected if it runs iOS/iPadOS version less than 14.8.1 or exactly 15.0, or macOS version less than 11.6.1.

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 11.6.1 / 14.8.1 or later
Fixed in 11.6.114.8.1
Interim mitigation

Update affected iOS/iPadOS devices to version 14.8.1 or later (or 15.1+) to apply the bounds checking fix.

Recommended fix High confidence

iOS 14.8.1, iPadOS 14.8.1, iOS 15.1, iPadOS 15.1, or macOS 11.6.1 (Security Update 2021-006)

  1. Identify the current version of iOS/iPadOS or macOS on the affected device by going to Settings > General > About (iOS/iPadOS) or Apple menu > About This Mac (macOS)
  2. For iPhone/iPad: Navigate to Settings > General > Software Update and download/install iOS 14.8.1 or iOS 15.1 (or iPadOS 14.8.1/15.1)
  3. For macOS: Navigate to System Preferences > Software Update and install macOS 11.6.1 (Security Update 2021-006) or later
  4. Alternatively, connect device to computer and update via Finder (iOS/iPadOS) or Finder/Recovery mode (macOS)
  5. After updating, verify the new version in Settings > General > About (iOS/iPadOS) or Apple menu > About This Mac (macOS)
Caveat Standard iOS/macOS update risks apply (ensure backups exist before updating); iOS 15 introduces UI changes that may require user adaptation

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

Fix this in Ipados Exploited in the wild — priority engagement
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing1.0 h
  • Review / QA1.0 h
5.0 hours of engineering $910
Get it fixed fast

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,456.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-30900 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2021-30900 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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