CVE-2026-92879 in vgmstream
Summary
by MITRE • 09/17/2026
A security flaw has been discovered in vgmstream up to r2117. This issue affects the function parse_mus of the file src/meta/mus_acm.c. The manipulation results in resource consumption. The attack may be launched remotely. The patch is identified as ae37662ad626254ddd96ad69ac263792d7a92024. Applying a patch is advised to resolve this issue.
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Analysis
by VulDB Data Team • 09/17/2026
The vulnerability in question resides within the vgmstream audio decoding library, specifically affecting versions up to revision r2117. This open-source tool is widely utilized for extracting and playing back audio from various video game formats, making it a critical component in many multimedia applications and security analysis tools. The flaw is located in the parse_mus function found within the source file src/meta/mus_acm.c. This specific module handles the decoding of audio files associated with the Sega Genesis/Mega Drive ACB/ACM format family. While vgmstream is generally designed to handle a wide array of legacy and modern game audio formats, its complexity introduces potential attack surfaces when processing malformed or maliciously crafted input data. The presence of this vulnerability highlights the inherent risks in parsing complex binary file structures without rigorous bounds checking and state validation during the initial stages of format interpretation.
The technical nature of this flaw centers on improper resource consumption resulting from manipulated inputs. When an attacker provides a specially constructed ACM audio file, the parse_mus function fails to adequately validate certain parameters or loop conditions before processing them. This lack of proper input sanitization allows for scenarios where the decoder enters infinite loops or allocates excessive memory resources during the parsing phase. Unlike vulnerabilities that lead directly to code execution via buffer overflows, this issue manifests as a denial-of-service condition through resource exhaustion. The system may become unresponsive or crash due to CPU saturation or out-of-memory errors when attempting to decode the maliciously crafted file. This type of flaw is particularly dangerous in server-side applications or automated scanning tools that process user-uploaded audio files without prior validation, as it can be leveraged to disrupt service availability for legitimate users.
From an operational perspective, this vulnerability poses a significant risk to any application integrating vgmstream for real-time audio processing or batch decoding tasks. Since the attack vector is remote, an adversary does not need local access to trigger the flaw; they simply need to deliver the malicious ACM file through networked services such as web uploads, email attachments with audio extensions, or streaming endpoints that utilize vgmstream under the hood. The impact extends beyond simple application crashes, potentially leading to cascading failures in dependent systems if resource limits are not strictly enforced at the operating system level. For organizations relying on this library for security research tools like game asset extractors or forensic analysis platforms, the inability to reliably process untrusted audio data undermines operational integrity and trustworthiness of the toolset.
To mitigate this risk, immediate application of patch ae37662ad626254ddd96ad69ac263792d7a92024 is strongly advised for all systems running vgmstream versions up to r2117. This patch addresses the underlying logic errors in the parse_mus function that lead to excessive resource consumption. Beyond applying the vendor-provided fix, organizations should implement defense-in-depth strategies such as sandboxing audio processing tasks within restricted environments with strict CPU and memory limits. Additionally, integrating input validation layers before passing files to vgmstream can help filter out malformed structures early in the pipeline. Security teams should also monitor for unusual spikes in resource usage associated with audio decoding processes, which may indicate active exploitation attempts against this vulnerability.
This incident aligns with common weakness enumeration standards such as CWE-400, which describes uncontrolled resource consumption leading to denial of service conditions. It also reflects patterns seen in the MITRE ATT&CK framework under techniques related to Resource Hijacking or Denial of Service via application layer attacks. By understanding these classifications, security professionals can better contextualize the threat and apply appropriate monitoring rules. Continuous integration pipelines should include fuzzing tests targeting audio parsers to detect similar logic errors before they reach production environments. Regular updates to third-party dependencies like vgmstream remain essential for maintaining a secure software supply chain against evolving exploitation techniques that target parsing routines in multimedia libraries.