Critical Vulnerability: CVE-2026-40189 — goshs — goshs

goshs is a SimpleHTTPServer written in Go. Prior to 2.0.0-beta.4, goshs enforces the documented per-folder .goshs ACL/basic-auth mechanism for directory listings and file reads, but it does not enforce the same authorization checks for state-changing routes. An unauthenticated attacker can upload files with PUT, upload files with multipart POST /upload, create directories with ?mkdir, and delete files with ?delete inside a .goshs-protected directory. By deleting the .goshs file itself, the attacker can remove the folder's auth policy and then access previously protected content without credentials. This results in a critical authorization bypass affecting confidentiality, integrity, and availability. This vulnerability is fixed in 2.0.0-beta.4.

CVE-2026-40189 is rated CRITICAL severity, requiring immediate attention from security teams.

CVSS Base Score: 9.8/10

EPSS (Exploit Prediction): 0.1% probability of exploitation in the next 30 days.

Vendors: goshs

Products: goshs

Use Vulnios to continuously monitor your exposure to CVE-2026-40189 and similar vulnerabilities.