Iphone OsOperating system · Apple

CVE-2021-30773

MEDIUM · 5.5 CVSS v3.1 Published 2021-09-08
Fix available
A fix is available. Upgrade to 7.6 / 14.7 or later.
See remediation →
58/100
Remediation priority · Elevated
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 issue in code signature validation was addressed with improved checks. This issue is fixed in iOS 14.7, tvOS 14.7, watchOS 7.6. A malicious application may be able to bypass code signing checks.

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-2021-30773 is a code signature validation bypass vulnerability in Apple's mobile operating systems (iOS, tvOS, watchOS). The vulnerability allows a malicious application to circumvent code signing checks, which are fundamental security mechanisms that verify the integrity and authenticity of executable code before execution. This could enable the execution of tampered or unauthorized code on affected devices.

MitigationApply the vendor-supplied security updates: iOS 14.7 (or later), tvOS 14.7 (or later), and watchOS 7.6 (or later). In enterprise environments, deploy updates via MDM (Mobile Device Management) systems and validate application compatibility post-update.

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
Iphone OsOperating system
Affected:< 14.7
TvosOperating system
Affected:< 14.7
WatchosOperating system
Affected:< 7.6

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
None
Integrity
High
Availability
None

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/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. Check iOS version on iPhone or iPad
    Open Settings > General > About on the device and look at the 'Version' field
    Affected if Version number is less than 14.7 (e.g., 14.6, 14.5, etc.)
  2. Check tvOS version on Apple TV
    Go to Settings > General > About on the Apple TV and view the version number shown
    Affected if Version number is less than 14.7 (e.g., 14.6, 14.5, etc.)
  3. Check watchOS version on Apple Watch
    On the Apple Watch, go to Settings > General > About and read the 'WatchOS' version; alternatively, open the Watch app on paired iPhone, go to My Watch > General > About
    Affected if Version number is less than 7.6 (e.g., 7.5, 7.4, etc.)

A device is affected if it runs iOS, tvOS, or watchOS versions prior to 14.7, 14.7, or 7.6 respectively, as only those versions contain the fix for the code signature validation bypass.

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 7.6 / 14.7 or later
Fixed in 7.614.7
Interim mitigation

Apply the vendor-supplied security updates: iOS 14.7 (or later), tvOS 14.7 (or later), and watchOS 7.6 (or later). In enterprise environments, deploy updates via MDM (Mobile Device Management) systems and validate application compatibility post-update.

Recommended fix High confidence

iOS 14.7, tvOS 14.7, or watchOS 7.6 (depending on device)

  1. Open Settings on your iPhone, Apple TV, or Apple Watch
  2. Tap General, then tap Software Update
  3. Download and install iOS 14.7 (for iPhone), tvOS 14.7 (for Apple TV), or watchOS 7.6 (for Apple Watch)
  4. Restart the device after the update completes
  5. Verify the update was successful by checking Settings > General > About > Version
Caveat Standard iOS/tvOS/watchOS upgrade considerations apply - some older apps may become incompatible, ensure backups exist before updating

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

Fix this in Iphone Os Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing4.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,080
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Scan for this in your stack

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dbcve dependency scanner

Check whether your project pulls in CVE-2021-30773 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-30773 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