CVE-2020-9900
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 issue existed within the path validation logic for symlinks. This issue was addressed with improved path sanitization. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10.15.6, tvOS 13.4.8, watchOS 6.2.8. A local attacker may be able to elevate their 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 · moderate confidenceA local privilege escalation vulnerability existed in Apple products due to improper path validation logic for symlinks. The flaw allowed a local attacker to manipulate symlink paths to bypass security controls and gain elevated privileges through improved path sanitization that was later implemented.
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< 13.6< 13.6< 10.15.6< 13.4.8< 6.2.8CVSS 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
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/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.
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Identify the Apple device and operating systemDetermine whether the system is an iPhone, iPad, Mac, Apple TV, or Apple Watch. On iOS/iPadOS, go to Settings > General > About. On macOS, go to Apple menu > About This Mac. On tvOS/watchOS, go to Settings > General > About.Affected if The device runs any of the affected Apple OS types (iOS, iPadOS, macOS, tvOS, watchOS).
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Check iOS or iPadOS versionOn the device, go to Settings > General > About and note the version number displayed next to 'Version'.Affected if The version is earlier than 13.6 (for iOS or iPadOS).
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Check macOS versionOn the Mac, click the Apple menu, select About This Mac, and note the version number shown (for example, 10.15.5).Affected if The version is earlier than 10.15.6.
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Check tvOS versionOn Apple TV, go to Settings > General > About > Version and note the build number.Affected if The version is earlier than 13.4.8.
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Check watchOS versionOn Apple Watch, open the Watch app on paired iPhone, go to General > About, and note the watchOS version.Affected if The version is earlier than 6.2.8.
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Confirm vulnerability applicabilityThis vulnerability requires local attacker access to manipulate symlink paths. Verify whether untrusted local users or processes have write access to directories where symlinks could be created.Affected if The OS version falls below the threshold AND the system allows untrusted local users to create or modify symlinks in sensitive paths.
A user is affected if their Apple device runs an OS version below the specific threshold (iOS/iPadOS 13.6, macOS 10.15.6, tvOS 13.4.8, or watchOS 6.2.8) and the symlink manipulation scenario applies to their environment.
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.
From vendor data6.2.810.15.613.4.8
Apply vendor-provided patches by updating to iOS 13.6+, iPadOS 13.6+, macOS 10.15.6+, tvOS 13.4.8+, or watchOS 6.2.8+ respectively. This is a patch deployment remediation requiring standard update procedures.
- Consultation4.0 h
- Implementation8.0 h
- Testing3.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-9900 — 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-2020-9900 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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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