Paper/Archive/CVE-2026-54089

CVE-2026-54089

filebrowser filebrowser — File Browser: Authentication Bypass via Proxy Auth Header Forgery

Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
filebrowser>= 2.0.0-rc.1–CNA

Scores by source

GitHub_M (CNA)9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA ADPSSVCExploitation: poc · Automatable: yes · Technical impact: total

References

exploitgithub.com/filebrowser/filebrowser/security/advisories/GHSA-xqp3-jq6g-x3qmrefgithub.com/filebrowser/filebrowser/blob/main/auth/proxy.gorefgithub.com/filebrowser/filebrowser/blob/main/http/auth.go#L121-L137