CVE-2021-34435

HIGH

Eclipse Theia < 1.8.1 - Permissive CORS Policy

Title source: rule
STIX 2.1

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..

Scores

CVSS v3 8.8
EPSS 0.0012
EPSS Percentile 31.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Details

CWE
CWE-942 CWE-346
Status published
Products (2)
eclipse/theia 0.3.9 - 1.8.1
theia/mini-browser 0.3.9 - 1.9.0npm
Published Sep 01, 2021
Tracked Since Feb 18, 2026