CVE-2020-27950A memory initialization issue was addressed.
Updated under an hour ago ()
Does this affect you?
It affects Apple watchOS and 4 other products. Add what you run to find out whether that includes you.
CISA lists it as known exploited since Nov 3, 2021; federal agencies had to remediate by May 3, 2022. Treat that date as your deadline.
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A memory initialization issue was addressed. This issue is fixed in macOS Big Sur 11.0.1, watchOS 7.1, iOS 12.4.9, watchOS 6.2.9, Security Update 2020-006 High Sierra, Security Update 2020-006 Mojave, iOS 14.2 and iPadOS 14.2, watchOS 5.3.9, macOS Catalina 10.15.7 Supplemental Update, macOS Catalina 10.15.7 Update. A malicious application may be able to disclose kernel memory.
- CVSS
- 5.5 MEDIUM (v3.1, CISA ADP)CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- Weakness (CWE)
- CWE-665
- Known exploited
- Added to CISA KEV Nov 3, 2021; federal remediation due May 3, 2022Apply updates per vendor instructions.
- EPSS (exploitation in the next 30 days)
- 16.52% (percentile 97)
- Assigned by
- apple
- NVD analysis
- Analyzed
- Record last updated
- Oct 21, 2025
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Apple watchOS apple:watchos (from the name) | from unspecified before 7.1 | CNA record |
Apple iOS and iPadOS apple:ios_and_ipados (from the name) | from unspecified before 14.2 | CNA record |
Apple macOS apple:macos (from the name) | from unspecified before 11.0 | CNA record |
apple ipados apple:ipados | before 14.2 | NVD |
apple iphone_os apple:iphone_os | before 12.4.9; from 14.0 before 14.2 | NVD |
apple macos apple:macos | before 10.15.7; from 11.0 before 11.0.1 | NVD |
apple watchos apple:watchos | before 5.3.9; from 6.0 before 6.2.9; from 7.0 before 7.1 | NVD |
References
- https://support.apple.com/en-us/HT211931x-refsource-misc, vendor-advisory
- https://support.apple.com/en-us/HT211928x-refsource-misc, vendor-advisory
- https://support.apple.com/en-us/HT211929x-refsource-misc, vendor-advisory
- https://support.apple.com/en-us/HT211940x-refsource-misc, vendor-advisory
- https://support.apple.com/en-us/HT211944x-refsource-misc, vendor-advisory
- https://support.apple.com/en-us/HT211945x-refsource-misc, vendor-advisory
- https://support.apple.com/en-us/HT211946x-refsource-misc, vendor-advisory
- https://support.apple.com/en-us/HT211947x-refsource-misc, vendor-advisory
- http://seclists.org/fulldisclosure/2020/Dec/32mailing-list, x-refsource-fulldisc, third-party-advisory
- http://packetstormsecurity.com/files/161296/XNU-Kernel-Mach-Message-Trailers-Memory-Disclosure.htmlx-refsource-misc, third-party-advisory, vdb-entry
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-27950us-government-resource
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.