CVE-2020-9934: Apple iOS, iPadOS, and macOS Input Validation Vulnerability

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: yes — in CISA KEV since 2022-09-08
EPSS: 3.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-10-16 · updated 2026-06-17

Description

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 products

Apple iPadOS: before 13.6 — fixed in 13.6
Apple Iphone Os: before 13.6 — fixed in 13.6
macOS: before 10.15.6 — fixed in 10.15.6

How to fix

Upgrade to a fixed version: Apple iPadOS 13.6; Apple Iphone Os 13.6; macOS 10.15.6. Check the vendor advisory for mitigations.

References

https://support.apple.com/HT211288
https://support.apple.com/HT211289
https://support.apple.com/HT211288
https://support.apple.com/HT211289
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-9934

Get alerted when CVE-2020-9934 or the next vulnerability affects your stack