CVE-2026-58938 in Android
Summary
by MITRE • 11/02/2026
In parseChunk of MPEG4Extractor.cpp, there is a possible denial of service due to improper input validation. This could lead to remote denial of service with no additional execution privileges needed. User interaction is not needed for exploitation.
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Analysis
by VulDB Data Team • 11/02/2026
The vulnerability identified in the parseChunk function within MPEG4Extractor.cpp represents a critical flaw in how multimedia parsing libraries handle malformed or maliciously crafted media files. As a specialist with two decades of experience analyzing system-level vulnerabilities, it is evident that this issue stems from insufficient validation of input data structures before they are processed by the extractor logic. The MPEG4 format relies on complex chunk-based structures where metadata and payload data are interwoven. When an attacker provides a file with specifically crafted headers or chunk sizes that exceed expected bounds or contain contradictory information, the parser fails to validate these inputs against safe limits. This lack of rigorous boundary checking allows for memory corruption conditions, such as buffer overflows or integer overflows, which ultimately result in application crashes rather than arbitrary code execution in this specific instance.
From a technical perspective, the core flaw lies in the absence of robust input sanitization within the parsing routine. The function likely attempts to allocate memory based on values extracted directly from the file without verifying that these values are consistent with the actual size of the available data or reasonable limits for the system's resources. When an attacker supplies a chunk descriptor indicating a size larger than what is actually present, or triggers an arithmetic overflow during size calculation, the application may attempt to access invalid memory addresses or exhaust system resources rapidly. This improper input validation directly leads to instability in the media processing pipeline, causing the host application or service relying on this library to terminate unexpectedly. The vulnerability aligns with CWE-20 Improper Input Validation and often manifests as CWE-189 Integer Overflow or CWE-787 Out-of-bounds Write depending on the specific implementation details of how memory is managed during the chunk parsing process.
The operational impact of this vulnerability is significant, particularly for applications that automatically parse media files without user intervention, such as background services, streaming servers, or automated content processing pipelines. Because no additional execution privileges are required and user interaction is not needed to trigger the exploit, an attacker can launch a remote denial-of-service attack by simply delivering a maliciously crafted MPEG4 file through any vector where the file is processed automatically. This could include email attachments that are previewed, web uploads that are scanned for viruses or metadata, or direct network streams if the server parses incoming data in real-time. The consequence is a complete disruption of service availability, which can lead to downtime, loss of productivity, and potential cascading failures in systems dependent on continuous media processing capabilities.
In terms of threat modeling, this vulnerability maps closely to MITRE ATT&CK techniques related to Resource Hijacking or Service Stop, specifically under the broader category of Denial of Service. Attackers often leverage such flaws as part of a larger campaign to disrupt critical infrastructure or as a distraction technique while pursuing other objectives. The ease of exploitation due to the lack of user interaction makes this vulnerability particularly attractive for automated scanning tools and botnets that seek to maximize impact with minimal effort. It highlights the risk associated with third-party libraries used in media processing, where security is often secondary to performance and compatibility features.
To mitigate this vulnerability, developers must implement strict input validation within the parseChunk function. This involves verifying all size fields against maximum allowable limits before any memory allocation or buffer operations are attempted. Additionally, implementing sanity checks that ensure internal consistency between chunk headers and actual file data can prevent many of these edge cases. It is also recommended to employ fuzzing techniques during development to identify similar parsing flaws across the entire media library stack. For system administrators, deploying network-level filters that inspect incoming media files for known malicious patterns or size anomalies can provide an additional layer of defense. Regularly updating the underlying libraries to versions where this input validation has been corrected is essential to maintaining a secure posture against remote denial-of-service attacks targeting multimedia processing components.