CVE-2023-20948 in Android
Summary
by MITRE • 02/28/2023
In dropFramesUntilIframe of AAVCAssembler.cpp, there is a possible out of bounds read due to a heap buffer overflow. This could lead to remote information disclosure with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-12 Android-12L Android-13Android ID: A-230630526
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Analysis
by VulDB Data Team • 09/05/2025
The vulnerability identified as CVE-2023-20948 represents a critical heap buffer overflow flaw within the Android multimedia processing framework, specifically within the AAVCAssembler.cpp component responsible for handling video frame assembly operations. This issue resides in the dropFramesUntilIframe function where improper bounds checking allows for out of bounds memory reads that can be exploited to extract sensitive information from the application's memory space. The vulnerability affects Android 12, 12L, and 13 operating system versions, making it a widespread concern across multiple Android releases that rely on the affected multimedia processing pipeline.
The technical implementation of this vulnerability stems from insufficient input validation during video frame processing operations where the system fails to properly verify array boundaries when processing video streams. When the dropFramesUntilIframe function processes incoming video data, it attempts to read memory locations beyond the allocated buffer boundaries, creating a condition where adjacent memory regions can be accessed and potentially disclosed. This heap buffer overflow occurs during the assembly of AVC (Advanced Video Coding) video streams, specifically when the system needs to skip frames until it encounters an iframe, a critical operation in video processing workflows. The flaw manifests as a direct consequence of improper memory management practices that fail to validate the length and boundaries of data being processed, allowing attackers to manipulate the video parsing logic to access unauthorized memory regions.
The operational impact of this vulnerability is significant as it enables remote information disclosure without requiring any additional execution privileges or user interaction for exploitation. Attackers can leverage this vulnerability by crafting malicious video content that triggers the vulnerable code path during normal video playback operations. The lack of user interaction requirements makes this particularly dangerous as it can be exploited through automated means during routine media consumption activities. The disclosed information could potentially include sensitive data such as cryptographic keys, personal user information, or application memory contents that could be used for further exploitation or privacy violations. This vulnerability directly relates to CWE-125, which describes out-of-bounds read conditions, and aligns with ATT&CK technique T1059.007 for execution through multimedia formats, making it a critical concern for Android device security.
Mitigation strategies for CVE-2023-20948 should focus on immediate patch application from Android security updates that address the buffer overflow condition through proper bounds checking and memory validation. Organizations should implement comprehensive monitoring for suspicious video content processing activities and consider network-level filtering of potentially malicious media files until patches are deployed. The fix typically involves strengthening input validation mechanisms within the AAVCAssembler.cpp file to ensure all buffer operations respect their allocated boundaries before any memory access occurs. Additionally, system administrators should prioritize updating affected Android devices to the latest security patches and consider implementing application sandboxing measures to limit the potential impact of information disclosure attacks. Security teams should also conduct thorough vulnerability assessments of multimedia processing components and establish incident response procedures specifically tailored to handle potential exploitation attempts targeting this class of buffer overflow vulnerabilities.