dbcve.org
IpadosOperating system · Apple

CVE-2021-1809

HIGH · 7.5 CVSS v3.1 Published 2021-09-08
Fix available
A fix is available. Upgrade to 7.4 / 11.3 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges 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 memory corruption issue was addressed with improved validation. 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. A malicious application may be able to read restricted memory.

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

This is a memory corruption vulnerability in Apple's core operating systems (macOS, iOS, iPadOS, watchOS, tvOS) where inadequate memory validation allows a malicious local application to read restricted memory regions. The issue is patched in the mentioned security updates.

MitigationApply the relevant security updates (iOS 14.5, iPadOS 14.5, macOS Big Sur 11.3, Security Update 2021-002/2021-003, watchOS 7.4, tvOS 14.5) to all affected devices and systems.

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, <= 10.14.5>= 10.15, <= 10.15.5= 10.14.6= 10.15.6= 10.15.7
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
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/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. Check macOS version on Mac computers
    Run 'sw_vers -productVersion' in Terminal or view System Preferences > About
    Affected if Version is 10.14.x up to 10.14.6, 10.15.x up to 10.15.7, or 11.0 to 11.2.x (below 11.3)
  2. Check iOS version on iPhones
    Go to Settings > General > About and note the version number, or run 'idevicesyslog' with device connected
    Affected if Version is below 14.5 (for example 14.4.x, 14.3, etc.)
  3. Check iPadOS version on iPads
    Go to Settings > General > About and note the version number
    Affected if Version is below 14.5
  4. Check tvOS version on Apple TV
    Go to Settings > General > About > Version
    Affected if Version is below 14.5
  5. Check watchOS version on Apple Watch
    Open the Watch app on paired iPhone, go to My Watch > General > About
    Affected if Version is below 7.4

If any Apple device runs an OS version lower than 14.5 (iOS/iPadOS/tvOS/watchOS) or lower than 11.3 (macOS Big Sur) or falls into the specific macOS X 10.14.x/10.15.x ranges listed, it is affected by this vulnerability.

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 security updates (iOS 14.5, iPadOS 14.5, macOS Big Sur 11.3, Security Update 2021-002/2021-003, watchOS 7.4, tvOS 14.5) to all affected devices and systems.

Recommended fix High confidence

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

  1. Identify the device type (iPhone, iPad, Mac, Apple Watch, Apple TV)
  2. Determine the current installed OS version from Settings > General > About (iOS/iPadOS) or System Preferences > Software Update (macOS)
  3. For iPhone/iPad: Go to Settings > General > Software Update and install iOS/iPadOS 14.5 or later
  4. For Mac: Open System Preferences > Software Update and install the appropriate security update (Security Update 2021-002 for Catalina, Security Update 2021-003 for Mojave, or macOS Big Sur 11.3 or later)
  5. For Apple Watch: Open the Watch app on iPhone > General > Software Update and install watchOS 7.4 or later
  6. For Apple TV: Go to Settings > System > Software Updates and install tvOS 14.5 or later
  7. After updating, verify the fix by checking that the OS version matches or exceeds the fixed release for your device
Caveat Standard OS update considerations apply - ensure backups exist before updating, some legacy applications may not be compatible with newer OS versions

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 / QA3.0 h
11.0 hours of engineering $1,960
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,136.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-1809 — 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-2021-1809 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