{"id":"CVE-2026-42091","state":"PUBLISHED","title":"goshs has Cross-Origin Arbitrary File Write via Missing CSRF on PUT and Wildcard CORS","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.","publishedAt":"2026-05-04T17:24:47.890Z","updatedAt":"2026-05-05T14:14:46.121Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["patrickhener goshs"],"affected":[{"vendor":"patrickhener","product":"goshs","versions":[{"version":"< 2.0.2","status":"affected"}]}],"references":["https://github.com/patrickhener/goshs/security/advisories/GHSA-rhf7-wvw3-vjvm","https://github.com/patrickhener/goshs/commit/0e715b94e10c3d1aa552276000f15f104dee2f32","https://github.com/patrickhener/goshs/releases/tag/v2.0.2"],"weaknesses":["CWE-352"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/42xxx/CVE-2026-42091.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-42091","state":"PUBLISHED","datePublished":"2026-05-04T17:24:47.890Z","dateUpdated":"2026-05-05T14:14:46.121Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-04-23T19:17:30.566Z"},"containers":{"cna":{"title":"goshs has Cross-Origin Arbitrary File Write via Missing CSRF on PUT and Wildcard CORS","descriptions":[{"lang":"en","value":"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":[{"vendor":"patrickhener","product":"goshs","versions":[{"version":"< 2.0.2","status":"affected"}]}],"references":[{"url":"https://github.com/patrickhener/goshs/security/advisories/GHSA-rhf7-wvw3-vjvm","name":"https://github.com/patrickhener/goshs/security/advisories/GHSA-rhf7-wvw3-vjvm","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/patrickhener/goshs/commit/0e715b94e10c3d1aa552276000f15f104dee2f32","name":"https://github.com/patrickhener/goshs/commit/0e715b94e10c3d1aa552276000f15f104dee2f32","tags":["x_refsource_MISC"]},{"url":"https://github.com/patrickhener/goshs/releases/tag/v2.0.2","name":"https://github.com/patrickhener/goshs/releases/tag/v2.0.2","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.5,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-352","lang":"en","description":"CWE-352: Cross-Site Request Forgery (CSRF)","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-05-04T17:24:47.890Z"},"source":{"advisory":"GHSA-rhf7-wvw3-vjvm","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/patrickhener/goshs/security/advisories/GHSA-rhf7-wvw3-vjvm","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-05T13:07:28.351435Z","id":"CVE-2026-42091","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-05-05T14:14:46.121Z"}}]}}}