CVE-2020-27950
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.
Key facts
- CVSS score
- 5.5 (v3.1)
- Severity
- MEDIUM
- CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N- Weakness (CWE)
- CWE-665
- EPSS score
- 16.5% (97th percentile)
- In CISA KEV
- Yes, added November 3, 2021
- In EU EUVD
- Yes (EUVD-2020-20443)
- Published
- December 8, 2020
- NVD last modified
- June 17, 2026
- Status
- Analyzed
CISA Known Exploited Vulnerability
Apple Multiple Products Memory Initialization Vulnerability
Added to the KEV catalog on November 3, 2021; federal remediation due May 3, 2022.
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2020-20443 in the EU Vulnerability Database. ENISA flags it as known exploited. Last updated in EUVD on October 21, 2025.
View on the EU Vulnerability DatabaseAffected products
- apple / ipados
- apple / iphone os
- apple / macos
- apple / watchos
Certified products that may be affected
1 FIPS 140 or Common Criteria certified product, from automated matching by sec-certs.org.
- Apple macOS 11 Big Sur: Contacts - Apple Inc. - Common Criteria CCEVS-VR-VID-11243-2022 - archived
References
- http://packetstormsecurity.com/files/161296/XNU-Kernel-Mach-Message-Trailers-Memory-Disclosure.html(Third Party Advisory, VDB Entry)
- http://seclists.org/fulldisclosure/2020/Dec/32(Mailing List, Third Party Advisory)
- https://support.apple.com/en-us/HT211928(Vendor Advisory)
- https://support.apple.com/en-us/HT211929(Vendor Advisory)
- https://support.apple.com/en-us/HT211931(Vendor Advisory)
- https://support.apple.com/en-us/HT211940(Vendor Advisory)
- https://support.apple.com/en-us/HT211944(Vendor Advisory)
- https://support.apple.com/en-us/HT211945(Vendor Advisory)
- https://support.apple.com/en-us/HT211946(Vendor Advisory)
- https://support.apple.com/en-us/HT211947(Vendor Advisory)
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-27950(US Government Resource)
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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