CVE-2026-42091
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.
Does this matter?
Lower severity and a low EPSS score (0.17%). Track it; it rarely justifies an emergency change on its own.
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 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
- EPSS
- 0.17% probability · 6th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-352
- Affected
- goshs/goshs
- Source
- security-advisories@github.com
References
- https://github.com/patrickhener/goshs/commit/0e715b94e10c3d1aa552276000f15f104dee2f32Patch
- 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
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.