High severity · published Sep 1, 2021
CVE-2021-34435
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
8.8
CVSS
0.6%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 48% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TH
Theia · Eclipse
0.3.9 through 1.8.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-34435
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-34435
Exploit
https://bugs.eclipse.org/bugs/show_bug.cgi?id=568018
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