CVE-2021-34436
In Eclipse Theia 0.1.1 to 0.2.0, it is possible to exploit the default build to obtain remote...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
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.
- Record
CVE-2021-34436- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-22, CWE-611
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2021-34436- Weakness
- CWE-611, CWE-22
- Updated
- 2026-11-02
EUVDEUVD-2021-21091 No score
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.
- Record
EUVD-2021-21091- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-8gpx-73gc-wq7c No score
In Eclipse Theia 0.1.1 to 0.2.0, it is possible to exploit the default build to obtain remote...
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.
- Record
GHSA-8gpx-73gc-wq7c- Weakness
- CWE-22, CWE-611
- Updated
- 2026-11-02
OSV
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.
- Record
CVE-2021-34436- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-34436 is a critical vulnerability (CVSS 9.8) in Eclipse Theia, published September 2, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.22%, the 82nd percentile. No source names a fixed version.