Security Resilience

CVE-2020-27932

Memory Safety in Apple Watchos ≤ 5.3.9

CISA KEVActive ExploitationEUVD ExploitedPublic PoCMemory Safety
Published
08 December 2020
Modified
27 October 2025
KEV Added
03 November 2021
Patch / advisory
View advisory
CVSS Score v3.1 7.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.10 96th percentile
Risk Priority 83 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2020-27932 is a high-severity Type Confusion (CWE-843) vulnerability in Apple Watchos. Its CVSS base score is 7.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Junk Data (T1001.001); ranked in the top 4% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

A type confusion vulnerability, identified as CWE-843, was present in the XNU kernel and addressed through improved state handling. It affected multiple Apple platforms, including macOS Big Sur prior to 11.0.1, macOS Catalina prior to the 10.15.7 Supplemental Update, macOS Mojave and High Sierra prior to Security Update 2020-006, iOS prior to 14.2 and 12.4.9, iPadOS prior to 14.2, and various watchOS releases up to 7.1, 6.2.9, and 5.3.9.

The flaw could be triggered by a malicious application running on the device. With local access and no privileges required beyond user interaction to launch the app, an attacker could achieve arbitrary code execution with full kernel privileges, resulting in complete system compromise.

Apple security advisories for the listed updates, including HT211928, HT211929, and HT211931, recommend installing the patches that resolve the issue in the affected operating systems. Public references also include exploit details posted to sites such as Packet Storm and Full Disclosure.

EU & UK References

Vulnerability Data

A type confusion issue was addressed with improved state handling. 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…

more

5.3.9, macOS Catalina 10.15.7 Supplemental Update, macOS Catalina 10.15.7 Update. A malicious application may be able to execute arbitrary code with kernel privileges.

CWE(s)
CWE-843
KEV Date Added
03 November 2021

Related Threats

MITRE ATT&CK Enterprise Techniques

T1001.001 Junk Data Command And Control
Adversaries may add junk data to protocols used for command and control to make detection more difficult.
attack.mitre.org →
T1003 OS Credential Dumping Credential Access
Adversaries may attempt to dump credentials to obtain account login and credential material, normally in the form of a hash or a clear text password.
attack.mitre.org →
T1003.005 Cached Domain Credentials Credential Access
Adversaries may attempt to access cached domain credentials used to allow authentication to occur in the event a domain controller is unavailable.
attack.mitre.org →
T1003.006 DCSync Credential Access
Adversaries may attempt to access credentials and other sensitive information by abusing a Windows Domain Controller's application programming interface (API)(Citation: Microsoft DRSR Dec 2017) (Citation: Microsoft GetNCCChanges) (Citati…
attack.mitre.org →
T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
attack.mitre.org →
T1011.001 Exfiltration Over Bluetooth Exfiltration
Adversaries may attempt to exfiltrate data over Bluetooth rather than the command and control channel.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

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CVE-2023-23529Same product: Apple Ipadosboth on KEV
CVE-2022-42856Same product: Apple Ipadosboth on KEV
CVE-2024-23222Same product: Apple Ipadosboth on KEV
CVE-2020-27930Same product: Apple Ipadosboth on KEV
CVE-2021-1789Same product: Apple Ipadosboth on KEV
CVE-2023-27930Same product: Apple Ipados
CVE-2023-32434Same product: Apple Ipadosboth on KEV
CVE-2019-8506Same product: Apple Icloudboth on KEV
CVE-2023-32439Same product: Apple Ipadosboth on KEV

Affected Assets

apple
icloud
≤ 11.5
apple
itunes
≤ 12.11
apple
ipados
≤ 14.2
apple
iphone os
≤ 12.4.9 · 14.0 — 14.2
apple
mac os x
≤ 10.15.7
apple
macos
11.0 — 11.0.1
apple
watchos
≤ 5.3.9 · 6.0 — 6.2.9 · 7.0 — 7.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.5.2
  • V15.3.5

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 partial match
blocks

Secure SDLC practices directly prevent type-confusion flaws via safe typing, static analysis, and code review while the control itself addresses many additional weaknesses.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.5.14 Information transfer partial match
removes
A.5.15 Access control partial match
removes
A.5.16 Identity management partial match
removes
A.5.17 Authentication information partial match
removes
A.5.18 Access rights partial match
removes
A.8.10 Information deletion partial match
removes

References