CVE-2018-13300 in FFmpeg
Summary
by MITRE
In FFmpeg 4.0.1, an improper argument (AVCodecParameters) passed to the avpriv_request_sample function in the handle_eac3 function in libavformat/movenc.c may trigger an out-of-array read while converting a crafted AVI file to MPEG4, leading to a denial of service and possibly an information disclosure.
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Analysis
by VulDB Data Team • 04/03/2023
The vulnerability identified as CVE-2018-13300 represents a critical flaw in FFmpeg version 4.0.1 that manifests during media file conversion processes, specifically when handling certain AVI files destined for MPEG4 format. This issue resides within the movenc.c file in the libavformat module, where improper handling of AVCodecParameters arguments leads to unpredictable behavior during the conversion workflow. The flaw occurs in the handle_eac3 function, which processes EAC3 audio data during media encoding operations, creating a dangerous scenario where malformed input can cause the application to access memory locations beyond the intended array boundaries.
The technical exploitation of this vulnerability stems from a lack of proper input validation and boundary checking within the avpriv_request_sample function call. When FFmpeg encounters a crafted AVI file containing malformed EAC3 audio parameters, the handle_eac3 function receives improperly structured AVCodecParameters that do not conform to expected memory layout expectations. This improper argument passing results in an out-of-array read operation that can traverse memory regions beyond the allocated buffer space, potentially accessing uninitialized memory locations or other data structures within the application's memory space. The vulnerability specifically targets the memory management practices during audio codec parameter handling, where insufficient bounds checking allows for arbitrary memory access patterns.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable information disclosure attacks. When the out-of-array read occurs, the application may inadvertently expose sensitive data from adjacent memory regions, including cryptographic keys, user credentials, or other confidential information stored in memory. This information disclosure aspect transforms what might initially appear as a denial of service vulnerability into a more serious security concern that could compromise system integrity and confidentiality. The vulnerability affects the conversion pipeline specifically when processing AVI files with EAC3 audio streams, making it particularly relevant for multimedia processing applications that handle diverse audio formats and require robust input validation mechanisms.
Mitigation strategies for CVE-2018-13300 should focus on implementing comprehensive input validation and memory boundary checking within the affected FFmpeg components. System administrators and developers should prioritize updating to FFmpeg versions that contain patches addressing this specific vulnerability, as the official fix involves strengthening parameter validation within the handle_eac3 function and ensuring proper bounds checking before memory access operations. The remediation approach aligns with CWE-129, which addresses improper validation of array index values, and follows ATT&CK technique T1059 for command and scripting interpreter usage patterns that may be exploited. Organizations should also implement defensive programming practices including input sanitization, memory access validation, and comprehensive testing of media processing pipelines to prevent similar vulnerabilities from manifesting in other components of their multimedia handling infrastructure.