Vulnerability Description
goshs is a SimpleHTTPServer written in Go. Prior to version 2.0.2, the PUT upload handler (httpserver/updown.go) lacks the CSRF token validation that was added to the POST upload handler during the CVE-2026-40883 fix. Combined with the unconditional Access-Control-Allow-Origin: * on the OPTIONS preflight handler (httpserver/server.go), any website can write arbitrary files to a goshs instance through the victim's browser — bypassing network isolation (e.g. localhost, internal network). This issue has been patched in version 2.0.2.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Goshs | Goshs | < 2.0.2 |
Related Weaknesses (CWE)
References
- https://github.com/patrickhener/goshs/commit/0e715b94e10c3d1aa552276000f15f104dePatch
- https://github.com/patrickhener/goshs/releases/tag/v2.0.2ProductRelease Notes
- https://github.com/patrickhener/goshs/security/advisories/GHSA-rhf7-wvw3-vjvmExploitVendor Advisory
- https://github.com/patrickhener/goshs/security/advisories/GHSA-rhf7-wvw3-vjvmExploitVendor Advisory
FAQ
What is CVE-2026-42091?
CVE-2026-42091 is a vulnerability with a CVSS score of 6.5 (MEDIUM). goshs is a SimpleHTTPServer written in Go. Prior to version 2.0.2, the PUT upload handler (httpserver/updown.go) lacks the CSRF token validation that was added to the POST upload handler during the CV...
How severe is CVE-2026-42091?
CVE-2026-42091 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-42091?
Check the references section above for vendor advisories and patch information. Affected products include: Goshs Goshs.