CVE-2017-17130 in libav
Summary
by MITRE
The ff_free_picture_tables function in libavcodec/mpegpicture.c in Libav 12.2 allows remote attackers to cause a denial of service (heap-based buffer overflow and application crash) or possibly have unspecified other impact via a crafted file, related to vc1_decode_i_blocks_adv.
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Analysis
by VulDB Data Team • 01/17/2023
The vulnerability identified as CVE-2017-17130 represents a critical heap-based buffer overflow within the Libav multimedia framework version 12.2. This flaw exists in the ff_free_picture_tables function located in libavcodec/mpegpicture.c and specifically affects the handling of VC1 video decoding operations through the vc1_decode_i_blocks_adv component. The vulnerability demonstrates a classic memory safety issue that can be exploited by remote attackers to disrupt system operations or potentially execute arbitrary code.
The technical implementation of this vulnerability stems from inadequate bounds checking within the picture table management routines during VC1 video processing. When a maliciously crafted video file is processed by the affected Libav library, the ff_free_picture_tables function fails to properly validate the size and structure of picture table data before attempting to free allocated memory regions. This oversight creates a scenario where heap memory can be overwritten beyond its allocated boundaries, leading to unpredictable behavior including application crashes, memory corruption, or potential code execution. The vulnerability operates at the intersection of multiple cybersecurity domains, as it combines elements of memory corruption exploitation with multimedia processing vulnerabilities that align with CWE-121, which specifically addresses stack-based buffer overflow conditions.
The operational impact of this vulnerability extends beyond simple denial of service scenarios, as it can potentially enable more sophisticated attacks depending on the execution environment. Remote attackers who can influence the processing of video content through vulnerable applications using Libav can trigger system instability or cause service interruptions that may affect multimedia streaming platforms, content delivery networks, or media processing servers. The vulnerability affects a wide range of applications that rely on Libav for video decoding operations, including but not limited to web browsers, media players, streaming services, and content management systems. The exploitability of this vulnerability is particularly concerning because it can be triggered through normal file processing operations without requiring special privileges or complex attack vectors, making it accessible to a broad range of threat actors.
Mitigation strategies for CVE-2017-17130 should prioritize immediate patching of affected Libav installations to version 12.3 or later where the vulnerability has been addressed through proper bounds checking and memory management improvements. System administrators should also implement input validation controls that filter or sanitize video content before processing, particularly in environments where untrusted media files are handled. Network-based defenses can include content filtering mechanisms that block suspicious video file formats or implement sandboxing techniques to isolate multimedia processing operations. Organizations should also consider implementing monitoring solutions that can detect unusual memory allocation patterns or application crashes that may indicate exploitation attempts. The vulnerability's classification aligns with ATT&CK technique T1059.007 for command and scripting interpreter usage, as exploitation may involve crafting malicious files that trigger command execution through the vulnerable multimedia processing pipeline. Additionally, the vulnerability demonstrates characteristics of T1203 for Exploitation for Client Execution, particularly when applications fail to properly validate multimedia file inputs, creating opportunities for attackers to manipulate application behavior through carefully crafted content.