How severe is CVE-2020-9934?

CVE-2020-9934 has a CVSS score of 5.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2020-9934?

Affected package information for CVE-2020-9934 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2020-9934?

No fixed version has been published for CVE-2020-9934 yet. Monitor the advisory for updates, apply mitigations recommended by the vendor, and use O3 Security to track when a fix becomes available in your stack.

Is CVE-2020-9934 actively exploited in the wild?

Yes. There are 5 known exploit references for CVE-2020-9934, including 4 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2020-9934?

CVE-2020-9934 has an EPSS (Exploit Prediction Scoring System) score of 2.1%, placing it in the 84th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

Is CVE-2020-9934 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2020-9934 (Apple iOS, iPadOS, and macOS Input Validation Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2022-09-08. CISA required all US federal civilian agencies to remediate this vulnerability by 2022-09-29. The required action was: Apply updates per vendor instructions. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

Which products and versions are affected by CVE-2020-9934?

CVE-2020-9934 affects apple ipados; apple iphone os; apple mac os x. Check the affected-products list on this page against your deployed version to confirm exposure.

When was CVE-2020-9934 published, and has it been updated?

CVE-2020-9934 was published on October 16, 2020 and was last updated on October 23, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CISA KEV·Added 2022-09-08 — agencies required to remediate by 2022-09-29

CVE-2020-9934

MEDIUM

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.…

Published

Oct 16, 2020

Updated

Oct 23, 2025

Affected

0 pkgs

Patched

None yet

Exploits

5 known

EPSS Exploitation Probability

via FIRST.org ↗

2.1%probability of exploitation in next 30 days

Lower Risk84th percentile0.00%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

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

3 products · 3 configurations

ipadosapple

< 13.6

range

iphone osapple

< 13.6

range

mac os xapple

< 10.15.6

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

An issue existed in the handling of environment variables. This issue wa…

github.comMetasploitAug 2021

An issue existed in the handling of environment variables. This issue wa…

github.comGithubJul 2020

An issue existed in the handling of environment variables. This issue wa…

cisa.govCISASep 2022

An issue existed in the handling of environment variables. This issue wa…

bleepingcomputer.comAPIJul 2022

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2020-9934 in your stack?

O3 detects CVE-2020-9934 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my stack How O3 SCA works