CVE-2026-42091

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 v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/patrickhener/goshs/commit/0e715b94e10c3d1aa552276000f15f104dee2f32	Patch
https://github.com/patrickhener/goshs/releases/tag/v2.0.2	Product Release Notes
https://github.com/patrickhener/goshs/security/advisories/GHSA-rhf7-wvw3-vjvm	Exploit Vendor Advisory
https://github.com/patrickhener/goshs/security/advisories/GHSA-rhf7-wvw3-vjvm	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:goshs:goshs:*:*:*:*:*:go:*:*

History

No history.

Information

Published : 2026-05-04 18:16

Updated : 2026-06-17 10:47

NVD link : CVE-2026-42091

Mitre link : CVE-2026-42091

CVE.ORG link : CVE-2026-42091

JSON object : View

Products Affected

goshs

goshs

CWE

CWE-352

Cross-Site Request Forgery (CSRF)

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