CVE-2026-40884 goshs: Empty-username SFTP password authentication bypass in goshs
An unauthenticated attacker can bypass SFTP password authentication in goshs when configured with an empty username, allowing unauthorized file 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-2026-40884?
CVE-2026-40884 is a critical authentication bypass vulnerability in patrickhener goshs, published on 21 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.6, goshs contains an SFTP authentication bypass when the documented empty-username basic-auth syntax is used. If the server is started with -b ':pass' together with -sftp, goshs accepts that configuration but does not install any SFTP password handler. As a result, an unauthenticated network attacker can connect to the SFTP service and access files without a password. This vulnerability is fixed in 2.0.0-beta.6.
Weakness: CWE-306
Which versions are affected by CVE-2026-40884?
6 open source packages ship an affected version, including github.com/patrickhener/goshs and github.com/patrickhener/goshs/v2. 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 |
github.com/patrickhener/goshs/v2 Go | All versions | 2.0.0 |
github.com/patrickhener/goshs/v2 Go | All versions | 2.0.0 |
github.com/patrickhener/goshs/v2 Go | All versions | 2.0.0 |
Products include Goshs Goshs.
How do I fix CVE-2026-40884?
Upgrade to a fixed version.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-40884 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40884 exists.
Other vulnerabilities in patrickhener 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-2026-40189 goshs has a file-based ACL authorization bypass in goshs state-changing routes
- CVE-2026-40903 Goshs - ArtiPACKED Vulnerability – GitHub Actions Credential Persistence
Sources
Also known as GHSA-c29w-qq4m-2gcv, GO-2026-5303.