CVE-2020-9934 Apple iOS, iPadOS, and macOS Input Validation Vulnerability
Apple iOS, iPadOS, and macOS contain an unspecified vulnerability involving input validation which can allow a local attacker to view sensitive user information.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 8 Sep 2022.
- Rated Medium severity (CVSS 5.5, scored by CISA).
- It has been in the catalogue for 1,520 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
An issue existed in the handling of environment variables. This issue was addressed with improved validation. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10.15.6. A local user may be able to view sensitive user information.
Affected Versions
| Product | Versions |
|---|---|
| Apple iOS | unspecified to before iOS 13.6 and iPadOS 13.6 |
| Apple macOS | unspecified to before macOS Catalina 10.15.6 |
From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for Apple iOS, iPadOS, and macOS. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
- 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
Not Sure If You Are Exposed?
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