CVEs / CVE-2020-9934

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

Known exploited in the CISA KEV catalog since 8 Sep 2022
medium 5.5 CVSS 3.1 (NVD)
EPSS 3.2% chance of exploitation in the next 30 days, higher than 88% of CVEs (30 Oct 2026)
Last changed at its sources 17 Jun 2026

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Summary

Apple iOS, iPadOS, and macOS contain an unspecified vulnerability involving input validation which can allow a local attacker to view sensitive user information.
CISA, Known Exploited Vulnerabilities catalog

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.
The CVE record, via NVD · published 16 Oct 2020 · NVD status: Analyzed

Affected and fixed versions

As stated by the CVE record (from the CNA)
Product	Affected	Fixed in
Apple iOS	from unspecified, before iOS 13.6 and iPadOS 13.6	iOS 13.6 and iPadOS 13.6
Apple macOS	from unspecified, before macOS Catalina 10.15.6	macOS Catalina 10.15.6

Exploitation

In CISA KEV since	8 Sep 2022
Due date for US federal agencies	29 Sep 2022
Used in ransomware campaigns	Unknown
Required action	Apply updates per vendor instructions.

Severity

CVSS 3.1	5.5 medium `CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N` Scored by NVD

References

CVE-2020-9934 on NVD
CVE-2020-9934 in the CISA KEV catalog
https://support.apple.com/en-us/HT211288 (cited by CISA)
https://support.apple.com/en-us/HT211289 (cited by CISA)
https://support.apple.com/HT211288 Release Notes, Vendor Advisory
https://support.apple.com/HT211289 Release Notes, Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-9934 US Government Resource

Sources

Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.

This product uses data from the NVD API but is not endorsed or certified by the NVD.