CVE-2026-77385: CWE-639: Authorization Bypass Through User-Controlled Key in zoriya Kyoo
Kyoo is a self-hosted media server focused on movies, series, and anime. Prior to 5.1.0, a registered user with the core.play permission could supply a base64-encoded filesystem path to the transcoder. The path handling in transcoder/src/api/path.go cleaned the value and checked only that it began with Settings.SafePath before getHash processed it, while transcoder/src/api/streams.go served the accepted path without verifying a Kyoo catalog record. This missing catalog-level authorization allowed the user to retrieve hidden, temporary, operational, or other uncataloged files beneath the media directory when the path was known or guessed. This vulnerability is fixed in 5.1.0.
AI Analysis
Technical Summary
Kyoo is a self-hosted media server for movies, series, and anime. Before version 5.1.0, the transcoder component accepted a base64-encoded filesystem path from users with core.play permission. The path was cleaned and checked only to start with a safe base path, but no catalog-level authorization was enforced before serving the file. This allowed users to bypass authorization controls and retrieve files not cataloged by Kyoo, including hidden or operational files under the media directory. The vulnerability is identified as CWE-639 (Authorization Bypass Through User-Controlled Key) and CWE-862 (Missing Authorization). It was fixed in version 5.1.0.
Potential Impact
An attacker with a registered user account and core.play permission could access files outside the intended catalog by supplying crafted paths. This could lead to unauthorized disclosure of hidden or operational files within the media directory. The CVSS 3.1 score is 4.3 (medium severity), reflecting limited confidentiality impact and no integrity or availability impact.
Mitigation Recommendations
Upgrade Kyoo to version 5.1.0 or later, where this authorization bypass vulnerability has been fixed. No other mitigation is required as the fix addresses the root cause.
CVE-2026-77385: CWE-639: Authorization Bypass Through User-Controlled Key in zoriya Kyoo
Description
Kyoo is a self-hosted media server focused on movies, series, and anime. Prior to 5.1.0, a registered user with the core.play permission could supply a base64-encoded filesystem path to the transcoder. The path handling in transcoder/src/api/path.go cleaned the value and checked only that it began with Settings.SafePath before getHash processed it, while transcoder/src/api/streams.go served the accepted path without verifying a Kyoo catalog record. This missing catalog-level authorization allowed the user to retrieve hidden, temporary, operational, or other uncataloged files beneath the media directory when the path was known or guessed. This vulnerability is fixed in 5.1.0.
CVSS v3.1
Score 4.3medium
Affected software
zoriya
Kyoo
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Kyoo is a self-hosted media server for movies, series, and anime. Before version 5.1.0, the transcoder component accepted a base64-encoded filesystem path from users with core.play permission. The path was cleaned and checked only to start with a safe base path, but no catalog-level authorization was enforced before serving the file. This allowed users to bypass authorization controls and retrieve files not cataloged by Kyoo, including hidden or operational files under the media directory. The vulnerability is identified as CWE-639 (Authorization Bypass Through User-Controlled Key) and CWE-862 (Missing Authorization). It was fixed in version 5.1.0.
Potential Impact
An attacker with a registered user account and core.play permission could access files outside the intended catalog by supplying crafted paths. This could lead to unauthorized disclosure of hidden or operational files within the media directory. The CVSS 3.1 score is 4.3 (medium severity), reflecting limited confidentiality impact and no integrity or availability impact.
Mitigation Recommendations
Upgrade Kyoo to version 5.1.0 or later, where this authorization bypass vulnerability has been fixed. No other mitigation is required as the fix addresses the root cause.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-08-20T19:36:13.806Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6aad759f55bf5e2cf54f35b6
Added to database: 09/18/2026, 17:32:15 UTC
Last enriched: 09/18/2026, 17:47:10 UTC
Last updated: 09/18/2026, 23:06:32 UTC
Views: 9
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