CVE-2021-30987
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 access issue was addressed with improved access restrictions. This issue is fixed in macOS Monterey 12.1. A device may be passively tracked via BSSIDs.
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 privacy vulnerability in macOS allowed devices to be passively tracked via BSSIDs (Basic Service Set Identifiers, which are MAC addresses of wireless access points). An attacker could observe BSSID information to track user location or device movement without the user's knowledge. The issue was addressed with improved access restrictions in macOS Monterey 12.1.
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>= 12.0, < 12.1CVSS 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
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:L/AC:L/PR:L/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 checksWork through these to decide whether this CVE applies to you.
-
Check installed macOS version via command lineOpen Terminal and run: sw_vers -productVersionAffected if The output shows version 12.0 (exactly) - note that versions 12.1 and later are not affected
-
Alternative: Check via System PreferencesClick the Apple menu, select About This Mac, and note the version number displayedAffected if The displayed version reads 12.0, indicating the vulnerable release
-
Verify the build number (optional confirmation)In Terminal, run: sw_vers -buildVersionAffected if Build number starts with 21A (the 12.0 release builds) confirms the vulnerable version
A device is affected only if it is running macOS Monterey version 12.0; version 12.1 and later include the access restrictions that prevent BSSID tracking.
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 · scoped12.1
Update affected macOS devices to macOS Monterey 12.1 or later to apply the access restrictions that prevent passive BSSID tracking.
macOS Monterey 12.1
- Back up your Mac using Time Machine or another backup method before updating
- Open System Preferences (or System Settings on macOS Ventura and later)
- Click on Software Update
- If macOS Monterey 12.1 is available, click Update Now or Upgrade Now to download and install it
- Follow the on-screen instructions to complete the installation
- Restart your Mac when prompted to complete the update
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,168.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-30987 — 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-2021-30987 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