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CVE-2026-54089

File Browser: Authentication Bypass via Proxy Auth Header Forgery

Published: Jun 25, 2026Updated: Jun 25, 2026 Sources: CVE List NVDCWE-287
9.1CRITICAL
NVD MITRE
EPSS Score
0.4%
Top 64.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
No Fix Available
Self-Check
Not available

Description

File Browser is a file managing interface for uploading, deleting, previewing, renaming, and editing files within a specified directory. Starting with 2.0.0-rc.1, when FileBrowser is configured with proxy authentication (auth.method=proxy), any unauthenticated attacker who can reach the server directly can impersonate any user - including admin - by sending a single forged HTTP header. No credentials are required. Additionally, specifying a non-existent username causes the server to automatically create a new user account, providing an account creation primitive with no authorization. This is an already known issue that has been documented in the documentation for several years, but has not been documented as a vulnerability before.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:NAvailability
None
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Weaknesses

CWE-287CWE-290

Affected Products

filebrowser
oss-project
filebrowserOn-prem
Web & CMS Plugins / site-builder

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Initial Access
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References

https://github.com/filebrowser/filebrowser/blob/main/auth/proxy.go
github.com
https://github.com/filebrowser/filebrowser/blob/main/http/auth.go#L121-L137
github.com
https://github.com/filebrowser/filebrowser/security/advisories/GHSA-xqp3-jq6g-x3qm
github.com

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