CVE-2018-9533 in Android
Summary
by MITRE
In ixheaacd_dec_data_init of ixheaacd_create.c there is a possible out of write read due to a missing bounds check. This could lead to remote code execution with no additional execution privileges needed. User interaction is needed for exploitation. Product: Android. Versions: Android-9. Android ID: A-112766520
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Analysis
by VulDB Data Team • 04/13/2020
The vulnerability identified as CVE-2018-9533 resides within the ixheaacd audio decoder component of Android 9.0 systems, specifically in the ixheaacd_dec_data_init function located in the ixheaacd_create.c source file. This flaw represents a critical security weakness that could potentially allow remote code execution under specific conditions. The vulnerability stems from a missing bounds check during data initialization processes, creating a scenario where memory operations could exceed allocated buffer boundaries. The affected component is part of the broader audio processing framework that handles various audio codecs and decoding operations within the Android operating system.
The technical nature of this vulnerability aligns with CWE-129, which addresses insufficient bounds checking, and more specifically relates to CWE-787, which deals with out-of-bounds write operations. The flaw manifests when the ixheaacd_dec_data_init function processes audio data without properly validating input parameters against buffer limits. This missing validation allows an attacker to craft malicious audio data that, when processed by the vulnerable decoder, could overwrite adjacent memory locations. The out-of-bounds write condition creates a potential pathway for arbitrary code execution since memory corruption can lead to control flow hijacking. Attackers could exploit this through specially crafted audio files or streams that trigger the vulnerable code path during normal audio processing operations.
The operational impact of CVE-2018-9533 extends beyond simple data corruption, as it enables remote code execution without requiring additional privileges or user interaction beyond the initial exploitation trigger. This makes the vulnerability particularly dangerous in environments where users might encounter malicious audio content through various channels such as email attachments, web downloads, or streaming services. The attack surface is broadened by the fact that the vulnerability exists within a core system component that handles audio processing across multiple applications and services. The Android platform's architecture means that successful exploitation could potentially compromise the entire system, as audio processing components often have significant system-level privileges. The vulnerability's classification as requiring user interaction for exploitation suggests that while the initial trigger might be automated, human intervention is still necessary to complete the attack chain.
Mitigation strategies for this vulnerability should encompass multiple layers of protection and system hardening measures. Android security patches addressing this issue would typically include bounds checking modifications to the ixheaacd_dec_data_init function, ensuring proper validation of input data against buffer boundaries before memory operations occur. System administrators should prioritize applying the latest security updates from Google and device manufacturers, as these patches contain the necessary code modifications to prevent the out-of-bounds write condition. Additional protective measures include implementing runtime memory protection mechanisms such as stack canaries, address space layout randomization, and data execution prevention techniques. Network-level controls could also help by filtering suspicious audio content and implementing strict content validation protocols for media files processed by the affected system components. Organizations should also consider implementing application whitelisting and monitoring systems to detect anomalous audio processing behavior that might indicate exploitation attempts. The vulnerability's presence in Android 9.0 highlights the importance of maintaining current security patches and implementing comprehensive security monitoring across all system components that handle multimedia processing.