CVE-2021-30807
A memory corruption issue was addressed with improved memory handling. This issue is fixed in macOS Big Sur 11.5.1, iOS 14.7.1 and iPadOS 14.7.1…
Browse: All 2021 CVEs · All vendors
- CVSS score
- 7.8 High
- CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H- CISA KEV
- Yes — actively exploited (added 2021-11-03, remediation due 2021-11-17)
- Weakness (CWE)
- CWE-787
- Published
- 2021-10-19
- Last modified
- 2026-06-17
- NVD status
- Analyzed
Description
A memory corruption issue was addressed with improved memory handling. This issue is fixed in macOS Big Sur 11.5.1, iOS 14.7.1 and iPadOS 14.7.1, watchOS 7.6.1. An application may be able to execute arbitrary code with kernel privileges. Apple is aware of a report that this issue may have been actively exploited.
Affected products
- apple ipados
- apple iphone os
- apple macos
- apple watchos
Affected ranges per NVD CPE data; confirm exact versions in the vendor advisory.
Required action (CISA)
Apply updates per vendor instructions. Federal remediation deadline: 2021-11-17.
How to prioritize this
This vulnerability is on the CISA KEV list, meaning it is being actively exploited — treat it as urgent regardless of the raw CVSS number. Use the live CVE lookup for the latest NVD data, and the CVSS 3.1 calculator to model your own environmental score. For the actively exploited vulnerabilities that matter this week, read The Exploit HQ daily security brief.
References
- https://support.apple.com/en-us/HT212622
- https://support.apple.com/en-us/HT212623
- https://support.apple.com/en-us/HT212713
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30807
FAQ
Is CVE-2021-30807 actively exploited?
Yes. CISA added CVE-2021-30807 to its Known Exploited Vulnerabilities (KEV) catalog on 2021-11-03, with a federal remediation deadline of 2021-11-17. A KEV listing means real-world exploitation is confirmed, so patching this should be prioritized above many higher-CVSS bugs that aren't being exploited.
What is the CVSS score of CVE-2021-30807?
CVE-2021-30807 has a CVSS base score of 7.8 (High). Its vector string is CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
Related vulnerabilities
- CVE-2026-86950 — Apple Multiple Products
- CVE-2025-43510 — Apple Multiple Products
- CVE-2025-43520 — Apple Multiple Products
- CVE-2025-31277 — Apple Multiple Products
- CVE-2023-43000 — Apple Multiple Products
- CVE-2021-30952 — Apple Multiple Products
Data source: NVD & CISA KEV. Shown as-is; nothing added. Last generated from NVD data — re-check the live tool for updates.
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