{"answers":{"affected":"7 open source packages ship an affected version, including github.com/patrickhener/goshs, github.com/patrickhener/goshs/v2 and goshs.de/goshs. It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42091 exists.","fix":"Upgrade to a fixed version.","what":"CVE-2026-42091 is a medium-severity vulnerability in patrickhener goshs, published on 4 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-42091 and fix it if it is affected.\n\nWhat it is: CVE-2026-42091 is a medium-severity vulnerability in patrickhener goshs, published on 4 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42091 exists.\n\nAffected packages and fixed versions:\n- github.com/patrickhener/goshs (Go): affected all versions; no fix listed\n- github.com/patrickhener/goshs (Go): affected all versions up to 1.1.4; no fix listed\n- github.com/patrickhener/goshs (Go): affected all versions up to 1.1.4; no fix listed\n- github.com/patrickhener/goshs/v2 (Go): affected all versions; fixed in 2.0.2\n- github.com/patrickhener/goshs/v2 (Go): affected all versions; fixed in 2.0.2\n- goshs.de/goshs (Go): affected all versions; no fix listed\n- goshs.de/goshs/v2 (Go): affected all versions; fixed in 2.0.2\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-42091/ (Markdown: https://insights.sbomify.com/CVE-2026-42091/index.md)","id":"CVE-2026-42091","markdown":"https://insights.sbomify.com/CVE-2026-42091/index.md","name":"CVE-2026-42091","record":{"aliases":["GHSA-rhf7-wvw3-vjvm","GO-2026-5625"],"analysis":{"component_type":"server_software","fix_type":"upgrade","impacts":["data_modify","security_bypass"],"network_reachable":"yes","non_default_config":false,"product_category":"Go HTTP server","requires_auth":"none","summary":"Attackers can write arbitrary files to goshs instances via CSRF and wildcard CORS, bypassing network isolation to modify data or execute code.","user_interaction":"required","vuln_class":"csrf"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"goshs","vendor":"goshs"}],"cvss":{"score":6.5,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","version":"3.1"},"cwes":[{"id":"CWE-352","name":"Cross-Site Request Forgery"}],"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.","ecosystems":["Go"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"goshs has Cross-Origin Arbitrary File Write via Missing CSRF on PUT and Wildcard CORS","id":"CVE-2026-42091","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Go","product":null,"products":[],"type":"csrf","year":"2026"},"n_packages":7,"n_references":3,"next":{"headline":"Global Settings Publication Exposes Sensitive Configuration to Any Authenticated User in Titra","id":"CVE-2026-42092"},"packages":[{"ecosystem":"Go","fixed":[],"introduced":["0"],"last_affected":[],"package":"github.com/patrickhener/goshs","purl":"pkg:golang/github.com/patrickhener/goshs","source":"GO-2026-5625"},{"ecosystem":"Go","fixed":[],"introduced":["0"],"last_affected":["1.1.4"],"package":"github.com/patrickhener/goshs","purl":null,"source":"GHSA-rhf7-wvw3-vjvm"},{"ecosystem":"Go","fixed":[],"introduced":["0"],"last_affected":["1.1.4"],"package":"github.com/patrickhener/goshs","purl":"pkg:golang/github.com/patrickhener/goshs","source":"GHSA-rhf7-wvw3-vjvm"},{"ecosystem":"Go","fixed":["2.0.2"],"introduced":["0"],"last_affected":[],"package":"github.com/patrickhener/goshs/v2","purl":null,"source":"GHSA-rhf7-wvw3-vjvm"},{"ecosystem":"Go","fixed":["2.0.2"],"introduced":["0"],"last_affected":[],"package":"github.com/patrickhener/goshs/v2","purl":"pkg:golang/github.com/patrickhener/goshs/v2","source":"GHSA-rhf7-wvw3-vjvm"},{"ecosystem":"Go","fixed":[],"introduced":["0"],"last_affected":[],"package":"goshs.de/goshs","purl":"pkg:golang/goshs.de/goshs","source":"GO-2026-5625"},{"ecosystem":"Go","fixed":["2.0.2"],"introduced":["0"],"last_affected":[],"package":"goshs.de/goshs/v2","purl":"pkg:golang/goshs.de/goshs/v2","source":"GO-2026-5625"}],"prev":{"headline":"Notesnook: RCE via stored XSS in note export rendering","id":"CVE-2026-42090"},"products":["goshs"],"published":"2026-05-04","related":[{"cvss_score":9.8,"headline":"goshs: Empty-username SFTP password authentication bypass in goshs","id":"CVE-2026-40884","kev_date_added":null,"published":"2026-04-21"},{"cvss_score":9.8,"headline":"goshs has an Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in goshs PUT Upload","id":"CVE-2026-35392","kev_date_added":null,"published":"2026-04-06"},{"cvss_score":9.8,"headline":"Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in goshs POST multipart upload","id":"CVE-2026-35393","kev_date_added":null,"published":"2026-04-06"},{"cvss_score":9.8,"headline":"Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in goshs","id":"CVE-2026-35471","kev_date_added":null,"published":"2026-04-06"},{"cvss_score":9.3,"headline":"goshs has a file-based ACL authorization bypass in goshs state-changing routes","id":"CVE-2026-40189","kev_date_added":null,"published":"2026-04-10"},{"cvss_score":9.1,"headline":"Goshs - ArtiPACKED Vulnerability – GitHub Actions Credential Persistence","id":"CVE-2026-40903","kev_date_added":null,"published":"2026-04-21"},{"cvss_score":8.7,"headline":"SFTP root escape via prefix-based path validation in goshs","id":"CVE-2026-40876","kev_date_added":null,"published":"2026-04-21"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"Go Vulnerability Database","prefix":"GO"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-05","vendors":["patrickhener"]},"summary":"Attackers can write arbitrary files to goshs instances via CSRF and wildcard CORS, bypassing network isolation to modify data or execute code.","url":"https://insights.sbomify.com/CVE-2026-42091/"}