CVE-2017-11549 in TiMidity++
Summary
by MITRE
The play_midi function in playmidi.c in TiMidity++ 2.14.0 allows remote attackers to cause a denial of service (large loop and CPU consumption) via a crafted mid file. NOTE: CPU consumption might be relevant when using the --background option.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 08/26/2025
The vulnerability identified as CVE-2017-11549 affects TiMidity++ version 2.14.0, specifically within the play_midi function located in the playmidi.c source file. This represents a denial of service weakness that can be exploited remotely through the manipulation of MIDI files. The flaw manifests when a maliciously crafted MIDI file is processed by the application, leading to excessive CPU consumption and potential system resource exhaustion. The vulnerability is particularly concerning because it can be triggered through standard MIDI file processing operations, making it accessible to attackers who can submit or upload such files to systems running the vulnerable software.
The technical implementation of this vulnerability stems from inadequate input validation and processing logic within the MIDI file parser. When TiMidity++ encounters a specially constructed MIDI file containing malformed loop structures or excessively long playback sequences, the play_midi function fails to properly handle these edge cases. The function processes loop markers and playback instructions without sufficient bounds checking, allowing maliciously designed loop constructs to cause the application to consume excessive CPU cycles. This behavior aligns with CWE-772, which describes insufficient resource management, and specifically relates to improper handling of recursive or iterative structures that can lead to resource exhaustion. The vulnerability is exacerbated when TiMidity++ is run with the --background option, as the daemonized process continues to consume system resources without user intervention, making the denial of service more persistent and difficult to detect.
The operational impact of this vulnerability extends beyond simple service disruption to potentially compromise system availability and performance. When exploited, the vulnerability can cause legitimate system processes to be starved of CPU resources, leading to degraded performance or complete system unresponsiveness. This is particularly problematic in server environments where TiMidity++ might be used to process audio files from untrusted sources, such as web applications or file upload systems. The vulnerability can be exploited through various attack vectors including web-based file uploads, email attachments, or direct file processing scenarios, making it a significant risk for systems that process external MIDI content. Organizations relying on TiMidity++ for audio processing or multimedia applications face potential downtime and service disruption when this vulnerability is successfully exploited, as the malicious MIDI files can cause sustained high CPU utilization that may require system restarts to resolve.
Mitigation strategies for CVE-2017-11549 should focus on both immediate defensive measures and long-term architectural improvements. The most effective immediate solution involves upgrading to a patched version of TiMidity++ that addresses the improper loop handling in the play_midi function. System administrators should also implement input validation controls that restrict the size and complexity of MIDI files processed by the application, particularly when handling untrusted content. Additional protective measures include implementing resource limits and process monitoring to detect and terminate abnormal CPU usage patterns, as well as configuring the application to avoid running with the --background option when possible. Security controls should also include network-level filtering to prevent unauthorized MIDI file uploads and implement proper access controls to limit who can submit files for processing. This vulnerability demonstrates the importance of proper input validation and resource management in multimedia processing applications, aligning with ATT&CK technique T1499.004 which covers network denial of service attacks through resource exhaustion, and reinforces the need for robust defensive programming practices in audio processing software.