CVE-2026-15276: Symphonia Metadata Handler Denial of Service Vulnerability

Technical summary

CVE-2026-15276 is a denial-of-service vulnerability in pdeljanov Symphonia up to version 0.6.0, located in the Metadata Handler component. The flaw stems from improper handling of metadata structures (CWE-404: Improper Resource Validation), allowing a local, low-privileged user to trigger a crash or hang without requiring user interaction. The CVSS 3.1 score of 3.3 reflects the local attack vector and the absence of confidentiality or integrity impact.

Business impact

This vulnerability has limited business risk in most environments because exploitation requires local system access and valid user credentials. The primary concern is service availability: if Symphonia is embedded in a critical audio pipeline or real-time media application, a malicious or negligent local user could interrupt service. Organizations using Symphonia in multi-tenant or shared-system contexts should evaluate whether a local denial-of-service poses operational risk. For single-user or air-gapped deployments, the impact is minimal.

Affected systems

pdeljanov Symphonia library versions up to and including 0.6.0 are affected. This is a dependency that may be embedded in audio processing applications, media players, or sound analysis tools written in Rust. End users should check their application vendors to confirm whether they bundle Symphonia and what versions they include. The vendor product list is not yet populated, indicating either limited known downstream usage or incomplete public disclosure of affected products.

Exploitability

Exploitation is straightforward but constrained: an attacker needs local system access and valid user privileges to trigger the denial of service via a specially crafted metadata input. A proof-of-concept has already been published, reducing the barrier to entry for someone with local access. However, the practical threat remains low because remote exploitation is not possible, and most systems have controls limiting who can log in locally and interact with the application.

Remediation

A pull request to fix this issue has been submitted to the Symphonia project but is awaiting maintainer acceptance. Monitor the official pdeljanov Symphonia repository for the merged patch and a subsequent release. Once a patched version is available, update Symphonia in your application's dependency tree. Until an official patch is released, implement access controls to restrict which local users can interact with Symphonia-based applications.

Patch guidance

Check the pdeljanov Symphonia GitHub repository for updates and merged pull requests addressing this metadata handling flaw. Once a new release is published with the fix, update your application's Symphonia dependency as soon as practical. Verify against the vendor advisory or release notes to confirm the fix is included. If you maintain or contribute to a downstream project that embeds Symphonia, prioritize updating after a stable fix is available. No interim mitigations can reliably prevent this without patching the underlying code.

Detection guidance

Look for crash logs or service hangs in applications running Symphonia when processing audio files with unusual or malformed metadata. Monitor process exit codes and resource utilization for Symphonia-based services. If you have source-code access, review your Symphonia version in dependency manifests (Cargo.toml for Rust projects). Intrusion detection on local systems could flag repeated attempts to feed crafted metadata, but this would require deep visibility into application input. Focus detection efforts on identifying which systems in your environment use Symphonia by scanning build artifacts and dependency declarations.

Why prioritize this

This vulnerability merits low prioritization in most security roadmaps. It requires local access, causes only denial of service, and has no confidentiality or integrity impact. Prioritize it higher only if your organization runs Symphonia-based services on shared or multi-tenant systems where local privilege boundaries are critical, or if service availability requirements are extremely strict. Even then, the impact is bounded to the Symphonia process or application, not the entire system.

Risk score, explained

The CVSS 3.1 score of 3.3 (LOW severity) reflects four key factors: (1) Attack Vector is Local, eliminating remote exploitability; (2) Attack Complexity is Low, meaning no special conditions are needed; (3) Privileges Required is Low, but still requires a valid local account; (4) Impact is limited to Availability (A:L), with no effect on confidentiality or integrity. The score appropriately weights a DoS that only affects a single application component accessible only to local users with some level of system access.

Frequently asked questions