CVE-2026-42091
goshs has Cross-Origin Arbitrary File Write via Missing CSRF on PUT and Wildcard CORS
- State
- Published
- Severity
- 6.5 Medium
- Published
- May 4, 2026
- Updated
- May 5, 2026
- Reserved
- Apr 23, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 6.5 Medium | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N | GitHub_M |
Weaknesses
- CWE-352 Cross-Site Request Forgery (CSRF)
Affected Products
| Product | Versions |
|---|---|
goshspatrickhener |
|
References
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