{"id":"CVE-2021-34435","aliases":["GHSA-v9w2-v7j9-rjpr"],"url":"https://o3.security/vulnerability/CVE-2021-34435","summary":"Remote code execution in Eclipse Theia","details":"In Eclipse Theia 0.3.9 to 1.8.1, the \"mini-browser\" extension allows a user to preview HTML files in an iframe inside the IDE. But with the way it is made it is possible for a previewed HTML file to trigger an RCE. This exploit only happens if a user previews a malicious file..","published":"2021-09-01T18:15:09.107Z","modified":"2026-08-07T17:02:17.545315Z","cvss":{"score":8.8,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":1,"affectedPackages":[{"ecosystem":"npm","name":"@theia/mini-browser","fixedVersion":"1.9.0"}],"fix":null,"references":[{"type":"FIX","url":"https://bugs.eclipse.org/bugs/show_bug.cgi?id=568018"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T17:02:17.545315Z"}}