CVE-2015-7810 in libbluray
Summary
by MITRE
libbluray MountManager class has a time-of-check time-of-use (TOCTOU) race when expanding JAR files
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 02/26/2024
The CVE-2015-7810 vulnerability resides within the libbluray library's MountManager class, which handles the mounting and expansion of JAR files during Blu-ray disc processing. This library serves as a critical component in Blu-ray playback systems, managing the extraction and organization of Java Archive files that contain multimedia content and interactive features. The vulnerability manifests as a time-of-check time-of-use race condition that occurs during the file expansion process, creating a window where system state can be manipulated between the initial validation and the actual file operations.
The technical flaw exploits a fundamental race condition pattern where the system performs a check to validate file integrity or permissions before proceeding with file operations. During this critical window, an attacker can manipulate the file system by replacing or modifying the JAR file or its dependencies, causing the MountManager to process malicious content instead of the intended legitimate files. This race condition specifically affects how the library handles file expansion operations, where the system checks file attributes and permissions before performing the actual extraction, but does not revalidate these conditions after the initial check.
The operational impact of this vulnerability extends beyond simple file manipulation, as it can potentially lead to arbitrary code execution within the context of the Blu-ray player application. Attackers could exploit this weakness by creating malicious JAR files that, when processed by the vulnerable MountManager, would execute unauthorized code during the expansion phase. This presents a significant security risk for Blu-ray playback systems, particularly those that process untrusted content or have automated JAR file handling capabilities. The vulnerability affects systems that rely on libbluray for Blu-ray disc processing, including media center applications, set-top boxes, and any software that utilizes this library for handling Blu-ray content.
Mitigation strategies for CVE-2015-7810 should focus on implementing proper file validation mechanisms that eliminate the race condition window. System administrators should ensure that all affected libbluray installations are updated to versions that address this specific race condition in the MountManager class. The fix typically involves revalidating file conditions after the initial check or implementing atomic file operations that prevent external manipulation during the expansion process. This vulnerability aligns with CWE-367, which addresses Time-of-Check to Time-of-Use race conditions, and may be categorized under ATT&CK technique T1059 for execution through command and scripting interpreters. Organizations should also implement proper access controls and file system monitoring to detect unauthorized file modifications that could exploit this weakness during the critical window period.