CVE-2021-30681
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 · uneditedA validation issue existed in the handling of symlinks. This issue was addressed with improved validation of symlinks. This issue is fixed in Security Update 2021-004 Mojave, iOS 14.6 and iPadOS 14.6, Security Update 2021-003 Catalina, macOS Big Sur 11.4, watchOS 7.5. A malicious application may be able to gain root 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 · high confidenceA validation vulnerability in symlink handling allows a malicious local application to escalate privileges to root. The flaw involves improper validation of symbolic links, which can be exploited to gain unauthorized elevated access.
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< 14.6< 14.6>= 10.14, <= 10.14.5>= 10.15, <= 10.15.6= 10.14.6= 10.15.7>= 11.0, < 11.4< 7.5CVSS 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 checksWork through these to decide whether this CVE applies to you.
-
Identify the macOS versionRun 'sw_vers -productVersion' in Terminal or check System Preferences > AboutAffected if The version is 10.14.x and <= 10.14.6, OR 10.15.x and <= 10.15.7, OR 11.x and < 11.4
-
Identify iOS or iPadOS versionGo to Settings > General > About on the device and note the version numberAffected if The version is less than 14.6
-
Identify watchOS versionOpen the Watch app on the paired iPhone, go to My Watch > General > AboutAffected if The version is less than 7.5
-
Confirm the vulnerable component is presentThis vulnerability is in the core symlink handling system component; if the OS version is vulnerable, the affected component is present by defaultAffected if The OS version matches any of the affected ranges listed in the CVE
A system is affected if it runs any macOS version 10.14 through 10.14.6, 10.15 through 10.15.7, or 11.0 through 11.3.x; or any iOS/iPadOS version below 14.6; or any watchOS version below 7.5.
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 · scoped7.511.414.6
Apply the relevant Apple security update: Security Update 2021-004 for Mojave, Security Update 2021-003 for Catalina, macOS Big Sur 11.4, iOS/iPadOS 14.6, or watchOS 7.5 to patch the symlink validation flaw.
iOS 14.6, iPadOS 14.6, macOS Big Sur 11.4, Security Update 2021-003 Catalina, Security Update 2021-004 Mojave, watchOS 7.5
- Identify the affected Apple device (iPhone, iPad, Mac, or Apple Watch)
- For iPhone/iPad: Go to Settings > General > Software Update and install iOS 14.6/iPadOS 14.6
- For Mac: Go to System Preferences > Software Update and install macOS Big Sur 11.4 or apply Security Update 2021-003 Catalina / Security Update 2021-004 Mojave as appropriate
- For Apple Watch: On the iPhone, open the Watch app, go to General > Software Update and install watchOS 7.5
- After updating, verify the device is running the fixed version
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation1.0 h
- Implementation2.0 h
- Testing1.0 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 $1,424.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-30681 — 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-2021-30681 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