CVE-2026-49339: gonic is a music streaming server / free-software subsonic server API implementation. The maintainer's fix in commit `6dd71e6a3c966867ef8c900d359a7df...

Description

gonic is a music streaming server / free-software subsonic server API implementation. The maintainer's fix in commit `6dd71e6a3c966867ef8c900d359a7df75789f410` added an ownership check based on `playlist.UserID`. However, `playlist.UserID` is derived from the first path segment of the attacker-controlled playlist ID, with no path containment on the resolved file path. Any authenticated Subsonic user can therefore bypass the ownership check and read any other user's playlist, delete any other user's playlist, and probe arbitrary file paths on the host for existence/readability. This is a bypass of the boundary the `6dd71e6` fix is trying to enforce; it is closely related to the original GONIC-1 IDOR but uses a different primitive (path traversal in the `id` parameter rather than direct cross-user access). Commit 0824bed88f6bbc490ba28bf09d28e5dfeb07b445 in version 0.21.0 fixes the issue.

Metrics

CVSS 3.1

7.1/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N

EPSS Probability

0.26%

17.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

References

Timeline

Published: Jun 19, 2026
Last Modified: Jun 23, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-49339?

gonic is a music streaming server / free-software subsonic server API implementation. The maintainer's fix in commit `6dd71e6a3c966867ef8c900d359a7df75789f410` added an ownership check based on `playlist.UserID`. However, `playlist.UserID` is derived from the first path segment of the attacker-controlled playlist ID, with no path containment on the resolved file path. Any authenticated Subsonic user can therefore bypass the ownership check and read any other user's playlist, delete any other user's playlist, and probe arbitrary file paths on the host for existence/readability. This is a bypass of the boundary the `6dd71e6` fix is trying to enforce; it is closely related to the original GONIC-1 IDOR but uses a different primitive (path traversal in the `id` parameter rather than direct cross-user access). Commit 0824bed88f6bbc490ba28bf09d28e5dfeb07b445 in version 0.21.0 fixes the issue.

How severe is CVE-2026-49339?

CVE-2026-49339 has a CVSS score of 7.1/10 (HIGH severity). The EPSS model estimates a 0.26% probability of exploitation in the next 30 days.

How do I fix CVE-2026-49339?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.