HomeCVE Intelligence › CVE-2026-62685
CVSS 8.1 HIGH Vulnerability

CVE-2026-62685: File Browser: Colliding username normalization gives two users the same home directory

Summary FileBrowser confines each user to a *scope*: a home directory that acts as the boundary for everything they can read or write. When self-registration and automatic home-directory creation are both enabled (Signu…

8.1CVSS Score
HIGHSeverity
NOCISA KEV
0.3%EPSS Score
VulnerabilityImpact Type

📋 Vulnerability Details

CVE IDCVE-2026-62685
Vendorgo
Affected Productgithub.com/filebrowser/filebrowser/v2
Vulnerability TypeVulnerability
CVSS Score8.1 (HIGH)
EPSS Score0.3% probability of exploitation in the next 30 days
Actively Exploited❌ No known exploitation
Patch StatusSee Vendor Advisory →
Reported ByCYBERDUDEBIVASH SENTINEL APEX Intelligence (via github_advisories)

🔬 Technical Analysis

#

Summary FileBrowser confines each user to a *scope*: a home directory that acts as the boundary for everything they can read or write. When self-registration and automatic home-directory creation are both enabled (Signup=true and CreateUserDir=true), a new user's scope is built from their username after it passes through cleanUsername(). That function rewrites the name: it strips .. and replaces every character outside 0-9A-Za-z@_\-. with -. The problem is that this rewrite is many-to-one: different usernames can produce the same result, and FileBrowser never checks whether the resulting scope is already taken. So team/one, team one, and team-one all collapse to the same directory name, and whoever registers second is handed the same home directory as the first

📚 Advisory References

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