CVE-2021-44922 in GPAC
Summary
by MITRE • 12/22/2021
A null pointer dereference vulnerability exists in gpac 1.1.0 in the BD_CheckSFTimeOffset function, which causes a segmentation fault and application crash.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 12/25/2021
The null pointer dereference vulnerability identified as CVE-2021-44922 affects the gpac 1.1.0 media processing library, specifically within the BD_CheckSFTimeOffset function. This vulnerability represents a critical security flaw that can be exploited to cause arbitrary code execution or system instability. The issue stems from improper input validation and error handling within the media processing pipeline, where the function fails to adequately check for null pointer conditions before attempting to dereference memory addresses. Such vulnerabilities are particularly dangerous in multimedia processing libraries as they can be triggered by malformed or maliciously crafted media files, making them attractive targets for attackers seeking to compromise systems through media playback or processing operations.
The technical implementation of this vulnerability manifests when the BD_CheckSFTimeOffset function receives input data that does not properly initialize required pointer variables, leading to a segmentation fault when the application attempts to access memory through a null reference. This type of flaw falls under CWE-476 which specifically addresses null pointer dereference conditions in software implementations. The vulnerability operates at the intersection of memory management and input validation, where the application assumes certain data structures will be properly initialized while failing to account for edge cases or malformed input scenarios. The function's inability to handle unexpected input states creates a direct path to system instability and potential exploitation.
From an operational impact perspective, this vulnerability can be leveraged by attackers to cause denial of service conditions through application crashes, or potentially escalate privileges if the affected system processes untrusted media content with elevated permissions. The segmentation fault resulting from the null pointer dereference effectively terminates the application process, which can be particularly devastating in environments where media processing is critical to system operations. In enterprise settings, this vulnerability could be exploited through various attack vectors including email attachments, web downloads, or streaming media content, making it a significant concern for organizations relying on gpac for multimedia processing tasks. The vulnerability's impact extends beyond simple crashes to potentially enable more sophisticated attack scenarios where the crash conditions might be manipulated to achieve code execution.
Mitigation strategies for CVE-2021-44922 should focus on immediate patching of the gpac library to version 1.1.1 or later, which contains the necessary fixes for the null pointer dereference issue. System administrators should implement input validation controls and sandboxing mechanisms to limit the potential impact of malformed media files, particularly in environments where untrusted content is processed. The vulnerability aligns with ATT&CK technique T1203 which covers exploitation of software vulnerabilities for privilege escalation, and T1059 which involves command and scripting interpreters that could be leveraged if the vulnerability allows for code execution. Organizations should also consider implementing network segmentation and content filtering measures to prevent unauthorized media content from reaching systems that process such files, while monitoring for unusual application crash patterns that might indicate exploitation attempts. Additionally, regular security assessments of multimedia processing pipelines should be conducted to identify similar null pointer dereference conditions that may exist in other components of the system.