CVE-2020-27224
Cross-site Scripting (XSS) in Eclipse Theia
In Eclipse Theia versions up to and including 1.2.0, the Markdown Preview (@theia/preview), can be exploited to execute arbitrary code.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
In Eclipse Theia versions up to and including 1.2.0, the Markdown Preview (@theia/preview), can be exploited to execute arbitrary code.
- Record
CVE-2020-27224- CVSS 3.1
- 9.6 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H - CVSS 2.0
- 9.3 High
AV:N/AC:M/Au:N/C:C/I:C/A:C - Weakness
- CWE-79
- Updated
- 2026-11-02
CVE List No score
In Eclipse Theia versions up to and including 1.2.0, the Markdown Preview (@theia/preview), can be exploited to execute arbitrary code.
- Record
CVE-2020-27224- Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2021-0825 No score
In Eclipse Theia versions up to and including 1.2.0, the Markdown Preview (@theia/preview), can be exploited to execute arbitrary code.
- Record
EUVD-2021-0825- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-gcm9-cc3r-c6vj
Cross-site Scripting (XSS) in Eclipse Theia
In Eclipse Theia versions up to and including 1.2.0, the Markdown Preview (@theia/preview), can be exploited to execute arbitrary code.
- Record
GHSA-gcm9-cc3r-c6vj- CVSS 3.1
- 9.6 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
In Eclipse Theia versions up to and including 1.2.0, the Markdown Preview (@theia/preview), can be exploited to execute arbitrary code.
- Record
CVE-2020-27224- CVSS 3.1
- 9.6 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
OSVGHSA-gcm9-cc3r-c6vj
Cross-site Scripting (XSS) in Eclipse Theia
In Eclipse Theia versions up to and including 1.2.0, the Markdown Preview (@theia/preview), can be exploited to execute arbitrary code.
- Record
GHSA-gcm9-cc3r-c6vj- CVSS 3.1
- 9.6 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
@theia/previewnpm |
before 1.2.0 | 1.2.0 |
@theia/previewnpm |
before 1.3.0 | 1.3.0 |
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-2020-27224 is a critical vulnerability (CVSS 9.6) in Eclipse Theia, published February 24, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.59%, the 85th percentile. Fixed in @theia/preview 1.2.0.