How severe is CVE-2020-9934?

CVE-2020-9934 has a CVSS 3.1 base score of 5.5 (MEDIUM). EPSS estimates a 3.2% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

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

CISA Known Exploited Vulnerabilities

Apple iOS, iPadOS, and macOS Input Validation Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV

2022-09-08

Remediation due

2022-09-29

Required action
Apply updates per vendor instructions.

CISA notes
https://support.apple.com/en-us/HT211288, https://support.apple.com/en-us/HT211289; https://nvd.nist.gov/vuln/detail/CVE-2020-9934

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.

Severity

CVSS 3.1 · CISA5.5 MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

SSVC · CISA-ADP

Exploitationactive

Automatableno

Technical impactpartial

Exploitation Context

as of October 15, 2026

All KEV statistics→

CISA added CVE-2020-9934 to the KEV catalog 692 days after its CVE record was published.
It is one of 95 Apple entries in the CISA KEV catalog, and one of 26 added in 2022.
Its current EPSS score (3.2%) is higher than that of 13% of CISA KEV entries.

Affected Products

Vendor	Product	Affected versions
Apple	Apple iOS	unspecified to <iOS 13.6 and iPadOS 13.6
Apple	Apple macOS	unspecified to <macOS Catalina 10.15.6

References

2 Links

Other references

Record Details

Published

2020-10-16

Last updated

2025-10-21

Assigner (CNA)

apple

Credited to

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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.