CVE-2020-9944 in macOS
Summary
by MITRE • 12/09/2020
An out-of-bounds read was addressed with improved bounds checking. This issue is fixed in macOS Big Sur 11.0.1, watchOS 7.0, tvOS 14.0, iOS 14.0 and iPadOS 14.0. An application may be able to read restricted memory.
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Analysis
by VulDB Data Team • 12/17/2020
This vulnerability represents a critical out-of-bounds read flaw that could potentially allow malicious applications to access restricted memory regions within Apple's operating systems. The issue affects multiple Apple platforms including macOS Big Sur, watchOS, tvOS, iOS, and iPadOS, indicating a widespread concern that spans the entire Apple ecosystem. The vulnerability stems from insufficient bounds checking mechanisms within the system's memory management operations, creating an exploitable condition where applications could access memory locations they should not be permitted to reach.
The technical nature of this flaw aligns with CWE-125, which describes out-of-bounds read conditions where programs access memory beyond the bounds of allocated buffers. This particular vulnerability demonstrates how inadequate input validation and memory boundary enforcement can create persistent security weaknesses. Attackers could potentially leverage this condition to read sensitive data from restricted memory areas, potentially extracting confidential information or system credentials that should remain protected from application-level access. The flaw exists in the core memory management subsystems of these operating systems, making it particularly dangerous as it could be exploited across multiple device types.
The operational impact of this vulnerability extends beyond simple data exposure, as it could enable sophisticated attacks that combine this memory read flaw with other exploitation techniques to achieve arbitrary code execution or privilege escalation. According to ATT&CK framework, this vulnerability could be categorized under T1059 for execution and potentially T1003 for credential access, as it provides a pathway for unauthorized memory access that could lead to broader system compromise. The vulnerability affects all supported versions of the mentioned operating systems, creating a significant attack surface that could be exploited by adversaries with varying skill levels. Organizations and users must understand that this flaw represents a fundamental breakdown in the memory protection mechanisms that are essential for maintaining system integrity and data confidentiality.
Apple's patch addressing this vulnerability demonstrates the company's commitment to maintaining robust security controls across its platform ecosystem. The fix required improvements to bounds checking mechanisms throughout the operating system's memory management architecture, ensuring that all applications properly validate memory access operations. The remediation approach aligns with industry best practices for preventing out-of-bounds memory access issues, requiring comprehensive system-wide updates to strengthen memory protection boundaries. Users should immediately install the available updates for their respective operating systems, as this vulnerability represents a significant risk that could be exploited in targeted attacks against high-value targets or in mass exploitation campaigns. The patch not only addresses the immediate memory read issue but also reinforces the underlying security architecture to prevent similar vulnerabilities from emerging in the future.