CVE-2021-45263 in GPAC
Summary
by MITRE • 12/22/2021
An invalid free vulnerability exists in gpac 1.1.0 via the gf_svg_delete_attribute_value function, which causes a segmentation fault and application crash.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 12/25/2021
The vulnerability identified as CVE-2021-45263 represents a critical memory management flaw within the gpac multimedia framework version 1.1.0. This issue manifests through the gf_svg_delete_attribute_value function, which handles the deletion of SVG attribute values within the graphics processing pipeline. The flaw constitutes a classic invalid free operation that occurs when the application attempts to free memory that has either already been freed or was never properly allocated, creating a dangerous condition that can lead to system instability and potential exploitation.
The technical execution of this vulnerability involves a specific code path where the SVG attribute value deletion mechanism fails to properly validate memory pointers before attempting deallocation. This invalid free condition triggers a segmentation fault that results in an immediate application crash, effectively causing a denial of service condition. The vulnerability demonstrates characteristics consistent with CWE-415, which describes double free errors, and CWE-416, which covers use after free conditions, both of which fall under the broader category of memory safety issues that represent significant threats to software stability and security.
From an operational impact perspective, this vulnerability affects any system utilizing gpac 1.1.0 for multimedia processing, particularly those handling SVG content or graphics rendering. The segmentation fault creates an immediate and complete application termination, disrupting user workflows and potentially affecting automated processes that depend on gpac functionality. The vulnerability is particularly concerning in environments where gpac is used as a library component within larger applications, as the crash can propagate through the entire system architecture.
The exploitation of this vulnerability aligns with ATT&CK technique T1499.004, which focuses on network denial of service attacks through application crashes, and T1595.001, which covers reconnaissance through information gathering that could reveal system vulnerabilities. Attackers could potentially leverage this flaw to disrupt services by repeatedly triggering the invalid free condition, leading to sustained denial of service conditions that impact availability of multimedia processing capabilities. The vulnerability's impact extends beyond simple crash conditions, as it represents a fundamental memory management failure that could potentially be chained with other exploits to achieve more sophisticated attack objectives.
Mitigation strategies for CVE-2021-45263 require immediate patching of gpac to version 1.1.1 or later, which contains the necessary fixes for the memory management issue. Organizations should also implement runtime protections such as address space layout randomization and stack canaries to reduce exploitability. Additionally, monitoring systems should be configured to detect and alert on application crashes or segmentation fault occurrences, as these events may indicate exploitation attempts. The vulnerability highlights the importance of regular security updates and thorough testing of multimedia libraries, particularly those handling user-supplied content, as SVG processing represents a common attack surface for memory corruption vulnerabilities.