CVE Vulnerabilities

CVE-2021-34435

Permissive Cross-domain Security Policy with Untrusted Domains

Published: Sep 01, 2021 | Modified: Nov 21, 2024
CVSS 3.x
8.8
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS 2.x
6.8 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu

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..

Weakness

The product uses a web-client protection mechanism such as a Content Security Policy (CSP) or cross-domain policy file, but the policy includes untrusted domains with which the web client is allowed to communicate.

Affected Software

Name Vendor Start Version End Version
Theia Eclipse 0.3.9 (including) 1.8.1 (including)

Extended Description

If a cross-domain policy file includes domains that should not be trusted, such as when using wildcards under a high-level domain, then the application could be attacked by these untrusted domains. In many cases, the attack can be launched without the victim even being aware of it.

Potential Mitigations

References