CVE-2026-40189 goshs has a file-based ACL authorization bypass in goshs state-changing routes
Unauthenticated attackers can bypass ACLs to upload, delete, or modify files in protected directories, potentially removing the ACL file to gain full access.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-40189?
CVE-2026-40189 is a critical missing authorization vulnerability in patrickhener goshs, published on 10 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-862
Which versions are affected by CVE-2026-40189?
3 open source packages ship an affected version, including github.com/patrickhener/goshs. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/patrickhener/goshs Go | All versions | None |
github.com/patrickhener/goshs Go | All versions to 1.1.4 | None |
github.com/patrickhener/goshs Go | All versions to 1.1.4 | None |
Products include Goshs Goshs.
How do I fix CVE-2026-40189?
Upgrade to a fixed version.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-40189 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40189 exists.
Other vulnerabilities in patrickhener goshs
- CVE-2026-40884 goshs: Empty-username SFTP password authentication bypass in goshs
- CVE-2026-35392 goshs has an Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in goshs PUT Upload
- CVE-2026-35393 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in goshs POST multipart upload
- CVE-2026-35471 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in goshs
- CVE-2026-40903 Goshs - ArtiPACKED Vulnerability – GitHub Actions Credential Persistence
Sources
Also known as GHSA-wvhv-qcqf-f3cx, GO-2026-5728.