CVE-2015-3777 in Mac OS X
Summary
by MITRE
Multiple buffer overflows in blued in the Bluetooth subsystem in Apple OS X before 10.10.5 allow local users to gain privileges via XPC messages.
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Analysis
by VulDB Data Team • 02/02/2025
The vulnerability identified as CVE-2015-3777 represents a critical security flaw within Apple's Bluetooth subsystem, specifically affecting the blued daemon component that manages Bluetooth services on macOS systems. This issue manifests as multiple buffer overflows that occur when processing XPC (Cross-Process Communication) messages, creating a pathway for local attackers to escalate their privileges within the operating system. The vulnerability exists in Apple OS X versions prior to 10.10.5, making a significant portion of the macOS user base susceptible to exploitation.
The technical root cause of this vulnerability lies in inadequate input validation within the Bluetooth daemon's message handling routines. When the blued process receives XPC messages containing malformed data, it fails to properly bounds-check buffer allocations, leading to memory corruption that can be exploited to execute arbitrary code with elevated privileges. This type of vulnerability maps directly to CWE-121, which describes stack-based buffer overflow conditions, and CWE-122, which covers heap-based buffer overflow scenarios. The flaw specifically impacts the XPC communication mechanism that allows different processes to interact securely, but the insufficient validation creates opportunities for attackers to overwrite critical memory locations.
The operational impact of CVE-2015-3777 is significant as it enables local privilege escalation attacks that can potentially compromise entire system operations. An attacker with low-privilege access could leverage this vulnerability to gain root-level privileges, effectively bypassing standard operating system security controls. This makes the vulnerability particularly dangerous in environments where multiple users share systems or where attackers might initially gain access through other means before escalating their privileges. The attack vector requires local system access, which means the vulnerability cannot be exploited remotely, but it represents a serious threat in scenarios where physical access is possible or where attackers have already compromised other system components.
From a threat modeling perspective, this vulnerability aligns with ATT&CK technique T1068, which describes the use of local privilege escalation techniques, and T1059, which covers the execution of malicious code through system processes. The exploitation process typically involves crafting specially crafted XPC messages that trigger the buffer overflow conditions, allowing attackers to manipulate the execution flow of the blued daemon. Organizations should implement immediate mitigations including updating to macOS 10.10.5 or later versions, which contain patches addressing the buffer overflow conditions. Additional defensive measures include monitoring for unusual XPC communication patterns and implementing process isolation for Bluetooth-related services to limit the potential impact of successful exploitation attempts.