CVE-2021-1739
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 parsing issue in the handling of directory paths was addressed with improved path 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 local user may be able to modify protected parts of the file system.
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 path validation vulnerability in Apple operating systems allows a local authenticated user to bypass directory path checks and modify protected parts of the file system. The issue stems from insufficient validation during path parsing, enabling path traversal attacks against protected system directories.
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< 14.5< 14.5>= 10.14, <= 10.14.5>= 10.15, <= 10.15.5= 10.14.6= 10.15= 10.15.6= 10.15.7>= 11.0, < 11.3< 14.5< 7.4CVSS 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
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:L/AC:L/PR:L/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.
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Identify the installed Apple operating system productRun 'sw_vers' on macOS, or go to Settings > General > About on iOS/iPadOS/tvOS/watchOS to determine the exact product name and version numberAffected if The product name and version cannot be determined or does not match any Apple OS in the affected list
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Check macOS versionRun 'sw_vers -productVersion' to get the exact macOS version number (e.g., 10.14.6, 10.15.7, 11.2)Affected if Version is 10.14.x and <= 10.14.6, OR 10.15.x and <= 10.15.7, OR >= 11.0 and < 11.3 (including 11.0, 11.1, 11.2)
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Check iOS or iPadOS versionGo to Settings > General > About and note the Version number (e.g., 14.4)Affected if Version number is less than 14.5 (e.g., 14.4, 14.3, 13.x, etc.)
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Check tvOS or watchOS versionGo to Settings > General > About on Apple TV or Apple Watch companion app to find the version numberAffected if Version is less than 14.5 for tvOS, or less than 7.4 for watchOS
If the installed OS version falls within any of the affected ranges (iOS/iPadOS/tvOS/watchOS < 14.5, macOS 10.14.x through 10.14.6, 10.15.x through 10.15.7, or macOS 11.0 through 11.2.x), the environment is affected by this path traversal vulnerability.
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 · scoped7.411.314.5
Apply the relevant Apple security updates: Security Update 2021-002 for Catalina, Security Update 2021-003 for Mojave, macOS Big Sur 11.3, iOS/iPadOS 14.5, watchOS 7.4, or tvOS 14.5 depending on the affected device.
iOS 14.5, iPadOS 14.5, watchOS 7.4, tvOS 14.5, macOS Big Sur 11.3, Security Update 2021-002 Catalina, Security Update 2021-003 Mojave
- Identify the affected Apple device from the list: iPhone, iPad, Mac, Apple Watch, or Apple TV
- For iPhone/iPad: Go to Settings > General > Software Update and install iOS/iPadOS 14.5 or later
- For Mac: Go to System Preferences > Software Update and install macOS Big Sur 11.3 or later, or install Security Update 2021-002 (Catalina) or Security Update 2021-003 (Mojave)
- For Apple Watch: On the iPhone companion app, go to General > Software Update and install watchOS 7.4 or later
- For Apple TV: Go to Settings > System > Software Updates and install tvOS 14.5 or later
- After updating, verify the installation was successful by checking the OS version in Settings
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation1.0 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 $1,936.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-1739 — 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-2021-1739 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
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- 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
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