{"cve":"CVE-2021-34435","nvd":{"published":"2021-09-01T18:15:09.107","modified":"2026-06-17T03:55:51.733","status":"Modified","description":"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..","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","score":8.8},"cwes":["CWE-346","CWE-942"],"references":["https://bugs.eclipse.org/bugs/show_bug.cgi?id=568018","https://bugs.eclipse.org/bugs/show_bug.cgi?id=568018"],"products":["eclipse:theia"],"source":"nvd","synced_at":"2026-10-19T21:21:57.125947417+00:00"},"epss":{"cve":"CVE-2021-34435","score":0.00595,"percentile":0.48473,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-v9w2-v7j9-rjpr","url":"https://osv.dev/vulnerability/GHSA-v9w2-v7j9-rjpr","summary":"Remote code execution in Eclipse Theia","modified":"2023-11-08T04:06:07.936867Z","packages":[{"ecosystem":"npm","name":"@theia/mini-browser","purl":"pkg:npm/%40theia/mini-browser","ranges":[">=0.3.9 <1.9.0"],"fixed":["1.9.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}