CVE-2026-27611
Received Received - Intake
Insecure Direct Object Reference in FileBrowser Quantum Allows Unauthorized Download

Publication date: 2026-02-25

Last updated on: 2026-02-27

Assigner: GitHub, Inc.

Description
FileBrowser Quantum is a free, self-hosted, web-based file manager. Prior to versions 1.1.3-stable and 1.2.6-beta, when users share password-protected files, the recipient can completely bypass the password and still download the file. This happens because the API returns a direct download link in the details of the share, which is accessible to anyone with JUST THE SHARE LINK, even without the password. Versions 1.1.3-stable and 1.2.6-beta fix the issue.
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Meta Information
Published
2026-02-25
Last Modified
2026-02-27
Generated
2026-06-16
AI Q&A
2026-02-25
EPSS Evaluated
2026-06-15
NVD
CVE-2026-27611
EUVD
EUVD-2026-8594
Affected Vendors & Products
Showing 3 associated CPEs
Vendor Product Version / Range
gtsteffaniak filebrowser_quantum to 1.1.3 (exc)
gtsteffaniak filebrowser_quantum From 1.2.0 (inc) to 1.2.6 (exc)
gtsteffaniak filebrowser_quantum 1.1.3
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-288 The product requires authentication, but the product has an alternate path or channel that does not require authentication.
CWE-287 When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
CWE-200 The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
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Executive Summary

This vulnerability affects FileBrowser Quantum versions prior to 1.1.3-stable and 1.2.6-beta. When users share files protected by a password, the API returns a direct download link within the share details. This direct download link can be accessed by anyone who has the share link, without needing to enter the password.

The issue occurs because the API endpoint `/public/api/shareinfo?hash=<share_hash>` returns detailed share information including a `downloadURL` field that contains a direct download link with an embedded token. This tokenized URL allows unauthorized users to bypass the password protection and download the file directly.

Impact Analysis

This vulnerability can lead to unauthorized access to files that were intended to be protected by a password. Anyone with the share link can bypass the password prompt and download the shared file directly.

As a result, sensitive or confidential information could be exposed to unintended recipients, potentially leading to data leaks or breaches.

Compliance Impact

I don't know

Detection Guidance

[{'type': 'paragraph', 'content': 'This vulnerability can be detected by checking if the API endpoint `/public/api/shareinfo?hash=<share_hash>` returns a JSON response containing a `downloadURL` field that allows direct file download without requiring a password.'}, {'type': 'paragraph', 'content': 'A suggested command to detect this on your system or network is to perform a GET request to the share info API endpoint with a known share hash and inspect the response for the presence of the direct download URL.'}, {'type': 'list_item', 'content': 'curl -s "https://example.com/public/api/shareinfo?hash=<share_hash>" | grep downloadURL'}, {'type': 'paragraph', 'content': 'If the `downloadURL` is present and accessible without authentication, it indicates the vulnerability is present.'}] [2]

Mitigation Strategies

The immediate mitigation step is to upgrade FileBrowser Quantum to version 1.1.3-stable or 1.2.6-beta or later, where this vulnerability has been fixed.

Until the upgrade can be applied, avoid sharing files with password protection using the vulnerable versions, or disable anonymous access on password-protected shares to prevent unauthorized direct downloads.

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