CVE-2021-30696
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 · uneditedAn attacker in a privileged network position may be able to misrepresent application state. This issue is fixed in macOS Big Sur 11.4, Security Update 2021-003 Catalina, Security Update 2021-004 Mojave. A logic issue was addressed with improved state management.
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 confidenceA logic flaw in macOS (Catalina, Mojave, Big Sur) allows an attacker with privileged network position to misrepresent application state through improper state management. The vulnerability stems from inadequate handling of application or connection state validation.
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>= 10.14, <= 10.14.5>= 10.15, <= 10.15.6= 10.14.6= 10.15.7>= 11.0, < 11.4CVSS 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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:H/PR:N/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 checksWork through these to decide whether this CVE applies to you.
-
Check installed macOS versionGo to Apple menu > About This Mac, or run 'sw_vers' in TerminalAffected if Version is 10.14.x through 10.14.5, 10.14.6, 10.15.x through 10.15.6, 10.15.7, or 11.0-11.3 (any version below 11.4 on Big Sur)
-
Identify network exposureReview network configuration: check if the system is directly exposed to untrusted networks, serves as a VPN endpoint, or uses public/unsecured Wi-Fi without firewall protectionAffected if System has direct network exposure to untrusted or hostile network segments
-
Verify security update statusCheck System Preferences > Software Update for available updates, or run 'defaults read /Library/Preferences/com.apple.SoftwareUpdate.plist' to inspect last update timestampAffected if No security update (2021-003 for Catalina, 2021-004 for Mojave, or 11.4 for Big Sur) has been installed
System is affected if running any macOS version in the 10.14-10.14.6, 10.15-10.15.7, or 11.0-11.3 range and has network exposure that allows an attacker to occupy a privileged position in the network path.
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 · scoped11.4
Apply the appropriate macOS security update: Big Sur 11.4, Security Update 2021-003 for Catalina, or Security Update 2021-004 for Mojave. Prioritize systems exposed to untrusted network segments.
macOS Big Sur 11.4+ | Security Update 2021-003 (Catalina) | Security Update 2021-004 (Mojave)
- Open System Preferences (or System Settings on macOS 11+)
- Click on 'Software Update' to check for available updates
- Install the latest security update: For macOS Big Sur (11.x): upgrade to 11.4 or later; For macOS Catalina (10.15): install Security Update 2021-003; For macOS Mojave (10.14): install Security Update 2021-004
- Restart the system when prompted to complete the update
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 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 $2,800.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-30696 — 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-2021-30696 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
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.
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