CVE-2026-42091
Last modified
CVE-2026-42091 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. 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. EPSS estimates a 0.17% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Goshs | Goshs | < 2.0.2 |
References
- https://github.com/patrickhener/goshs/releases/tag/v2.0.2Product, Release Notes
- https://github.com/patrickhener/goshs/security/advisories/GHSA-rhf7-wvw3-vjvmExploit, Vendor Advisory
- https://github.com/patrickhener/goshs/security/advisories/GHSA-rhf7-wvw3-vjvmExploit, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
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