What is CVE-2021-30857?

CVE-2021-30857 is a high-severity vulnerability in Apple Ipados, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.0/10. Published 2021-08-24.

How severe is CVE-2021-30857?

High severity. CVSS v3 base score is 7.0 out of 10.

Vulnerability in Apple Ipados

CVE-2021-30857

A race condition was addressed with improved locking. This issue is fixed in Security Update 2021-005 Catalina, iOS 14.8 and iPadOS 14.8, tvOS 15, iOS 15 and iPadOS 15, watchOS 8, macOS Big Sur 11.6. A malicious application may be able to execute arbitrary code with kernel privileges.

Vulnerability class: Race Condition

Published 2021-08-24 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.0 (High). Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.009 (58.7th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 59th percentile — 58.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Apple Ipados
Apple Iphone OS
Apple macOS — versions unspecified
Apple Mac OS X — versions 10.15.7
Apple tvOS
Apple watchOS

Weakness classification (CWE)

CWE-362 — Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition)

References

Frequently asked questions

What is CVE-2021-30857?: CVE-2021-30857 is a high-severity vulnerability in Apple Ipados, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.0/10. Published 2021-08-24.
How severe is CVE-2021-30857?: High severity. CVSS v3 base score is 7.0 out of 10.