CVE-2021-33366 in GPAC
Summary
by MITRE • 09/14/2021
Memory leak in the gf_isom_oinf_read_entry function in MP4Box in GPAC 1.0.1 allows attackers to read memory via a crafted file.
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Analysis
by VulDB Data Team • 09/16/2021
The vulnerability identified as CVE-2021-33366 represents a memory leak condition within the MP4Box component of the GPAC multimedia framework version 1.0.1. This flaw manifests specifically within the gf_isom_oinf_read_entry function, which processes object information entries in mp4 files. The issue arises when the software encounters a specially crafted mp4 file that triggers improper memory management during the parsing of object information boxes. The memory leak occurs because the function fails to properly release allocated memory resources when processing malformed input data, creating a condition where memory consumption gradually increases with each processed file.
The technical exploitation of this vulnerability involves crafting a malicious mp4 file that contains malformed object information entries designed to trigger the memory leak in the gf_isom_oinf_read_entry function. When MP4Box attempts to parse this crafted file, the function processes the malformed data without proper memory deallocation, leading to a gradual accumulation of memory usage. This memory leak can be leveraged by attackers to consume system resources progressively, potentially leading to denial of service conditions where the application exhausts available memory. The vulnerability falls under CWE-401, which specifically addresses improper management of memory allocation and deallocation, making it a classic example of memory management flaws in software applications.
From an operational perspective, this vulnerability poses significant risks to systems that process mp4 files, particularly those that automatically handle or preview multimedia content. The memory leak can be exploited in various attack scenarios including web-based file processing systems, content management platforms, and multimedia applications that rely on GPAC for mp4 file handling. The impact extends beyond simple resource exhaustion as the progressive memory consumption can degrade system performance and potentially crash applications that are not designed to handle memory leaks gracefully. Attackers can repeatedly process malicious files to amplify the memory consumption effect, making this vulnerability particularly dangerous in environments where automated processing occurs.
The mitigation strategies for CVE-2021-33366 should focus on immediate software updates to GPAC version 1.0.2 or later, which contains the patched implementation of the gf_isom_oinf_read_entry function. Organizations should implement strict file validation procedures that scan mp4 files for malformed structures before processing them through GPAC components. Network security measures including content filtering and sandboxing of multimedia file handling processes can provide additional protection layers. The ATT&CK framework categorizes this vulnerability under T1059, which involves the execution of malicious code through file processing, and T1499, which covers resource hijacking through memory exhaustion attacks. Regular security monitoring and memory usage tracking should be implemented to detect potential exploitation attempts, while system administrators should consider implementing rate limiting and automated alerting for unusual memory consumption patterns in applications that handle multimedia files.