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.
Affected products
goshs: goshs
References4
- github.com/patrickhener/goshs/security/advisories/GHSA-rhf7-wvw… ExploitVendor Advisory
- github.com/patrickhener/goshs/security/advisories/GHSA-rhf7-wvw… ExploitVendor Advisory
- github.com/patrickhener/goshs/commit/0e715b94e10c3d1aa552276000… Patch
- github.com/patrickhener/goshs/releases/tag/v2.0.2 ProductRelease Notes
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N - EPSS — exploit probability
- 0% percentile: 6 · as of 13 November 2026
- CWE
- CWE-352
Could this be exploited in your environment?
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