CVE-2017-15847 in Android
Summary
by MITRE
In Android for MSM, Firefox OS for MSM, QRD Android, with all Android releases from CAF using the Linux kernel, in the SPCom kernel driver, a race condition exists when creating a channel.
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Analysis
by VulDB Data Team • 12/21/2019
The vulnerability identified as CVE-2017-15847 represents a critical race condition flaw within the SPCom kernel driver component of Android-based systems developed by Qualcomm. This issue affects multiple Android releases from CAF (Qualcomm Automotive Framework) that utilize the Linux kernel, including various MSM (Multi-System Module) platforms and Firefox OS for MSM devices. The race condition manifests during the channel creation process, creating a window of opportunity for malicious actors to exploit the system's timing vulnerabilities. The flaw resides in the kernel-level driver responsible for communication protocols, making it particularly dangerous as it operates at the core of system functionality and can potentially affect device stability and security.
The technical implementation of this race condition occurs when multiple processes or threads attempt to create communication channels simultaneously within the SPCom driver. During this process, the driver fails to properly synchronize access to shared resources or state variables, allowing for unpredictable behavior when concurrent channel creation requests are processed. The underlying mechanism involves improper locking mechanisms or atomic operations that should prevent multiple threads from accessing critical sections of code simultaneously. This flaw can be exploited by an attacker who can time their actions to trigger the race condition, potentially leading to memory corruption, privilege escalation, or denial of service conditions. The vulnerability aligns with CWE-362, which specifically addresses race conditions in concurrent programming, and can be categorized under ATT&CK technique T1068, involving exploit for privilege escalation.
The operational impact of this vulnerability extends across multiple device categories including smartphones, tablets, and automotive systems that rely on Qualcomm's MSM platforms. Attackers could potentially exploit this flaw to gain elevated privileges within the kernel space, allowing them to execute arbitrary code with system-level permissions. The race condition could also lead to system instability, causing unexpected reboots or crashes that affect device availability. In automotive applications, this vulnerability could pose significant safety risks as it may compromise the integrity of communication systems between vehicle components and external networks. The widespread adoption of Qualcomm's MSM platforms across various Android devices means that numerous users could be affected by this vulnerability, particularly those running older Android versions that may not have received security patches for this specific issue.
Mitigation strategies for CVE-2017-15847 should focus on implementing proper synchronization mechanisms within the SPCom driver code to prevent concurrent access to shared resources during channel creation. System administrators and device manufacturers should prioritize applying security patches provided by Qualcomm and Google to address the race condition in the kernel driver. Additionally, runtime monitoring systems can be deployed to detect anomalous behavior patterns that may indicate exploitation attempts. The implementation of kernel-based mitigations such as stack canaries, address space layout randomization, and enhanced memory protection mechanisms can provide additional layers of defense. Organizations should also conduct thorough vulnerability assessments of their Android-based systems to identify potential exposure to similar race condition vulnerabilities, while maintaining updated threat intelligence to monitor for any exploitation attempts targeting this specific flaw.