CVE-2020-9978 in watchOS
Summary
by MITRE • 04/03/2021
This issue was addressed with improved setting propagation. This issue is fixed in macOS Big Sur 11.0.1, tvOS 14.0, macOS Big Sur 11.1, Security Update 2020-001 Catalina, Security Update 2020-007 Mojave, watchOS 7.0, iOS 14.0 and iPadOS 14.0. An attacker in a privileged network position may be able to unexpectedly alter application state.
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Analysis
by VulDB Data Team • 04/08/2021
CVE-2020-9978 represents a vulnerability in Apple's operating systems that stems from inadequate handling of setting propagation mechanisms within the system architecture. This flaw allows an attacker positioned within a privileged network location to manipulate application state in unexpected ways, potentially leading to unauthorized modifications of system configurations or application behavior. The vulnerability specifically affects the way system settings are propagated across different components of Apple's ecosystem, creating a pathway for malicious actors to exploit the trust relationships between system processes. The issue manifests when the system fails to properly validate or enforce the integrity of setting changes, enabling an attacker to inject malicious configurations that persist across application boundaries.
The technical nature of this vulnerability aligns with CWE-284, which addresses improper access control in system settings and configuration management. This weakness occurs at the system-level configuration propagation layer where proper validation mechanisms fail to prevent unauthorized modifications to application state. The vulnerability demonstrates a classic privilege escalation vector through network-based attacks, where an attacker with access to a privileged network position can observe and manipulate the flow of system settings. The flaw operates by exploiting the trust model that exists between different system components when processing configuration changes, allowing an attacker to inject modified settings that bypass normal validation procedures. This creates a persistent threat where compromised settings can affect multiple applications and system services that rely on the propagated configuration values.
The operational impact of CVE-2020-9978 extends beyond simple configuration manipulation to potentially enable broader system compromise. When an attacker can alter application state through setting propagation, they gain the ability to modify security policies, change user permissions, or redirect application behavior in ways that could facilitate further attacks. The vulnerability affects multiple Apple platforms including macOS, iOS, watchOS, and tvOS, creating a widespread attack surface that requires coordinated patching across the entire ecosystem. This cross-platform nature of the vulnerability makes it particularly dangerous as it can be exploited across different device types and operating system versions, potentially allowing attackers to establish persistent footholds in environments where multiple Apple devices are interconnected.
Mitigation strategies for CVE-2020-9978 primarily involve applying the vendor-provided security updates that address the setting propagation mechanisms. Apple's release of Security Update 2020-001 for Catalina, Security Update 2020-007 for Mojave, and the respective updates for Big Sur, iOS 14, and watchOS 7.0 contain the necessary fixes to resolve the vulnerability. Organizations should prioritize deployment of these updates across all affected systems to prevent exploitation. Network administrators should also implement monitoring solutions to detect unusual setting changes or propagation patterns that might indicate exploitation attempts. The vulnerability's classification under ATT&CK technique T1546.008 for 'Rundll32' and related privilege escalation techniques indicates that exploitation may involve manipulation of system-level processes that handle configuration changes. Additional defensive measures include implementing network segmentation to limit privileged network access and conducting regular security audits to verify that system settings remain within expected parameters.