CVE-2021-34436

Description

In Eclipse Theia 0.1.1 to 0.2.0, it is possible to exploit the default build to obtain remote code execution (and XXE) via the theia-xml-extension. This extension uses lsp4xml (recently renamed to LemMinX) in order to provide language support for XML. This is installed by default.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 3.50% Top 15%
Vendor Advisory eclipse.org
Affected: The Eclipse Foundation Eclipse Theia
Published at:
Updated at:

References

Link Tags
https://bugs.eclipse.org/bugs/show_bug.cgi?id=563174 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-34436?
CVE-2021-34436 has been scored as a critical severity vulnerability.
How to fix CVE-2021-34436?
To fix CVE-2021-34436, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-34436 being actively exploited in the wild?
It is possible that CVE-2021-34436 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~4% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-34436?
CVE-2021-34436 affects The Eclipse Foundation Eclipse Theia.
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