CVE-2026-12856

Vscode-java: vscode: command injection vulnerability in the javadoc hover provider of the vscode-java extension

Published Jun 29, 2026 CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed
Description
A flaw was found in the vscode-java extension, which provides Java language support for Visual Studio Code. The extension incorrectly trusts all Markdown content in JavaDoc hovers, allowing a malicious Java file to include hidden commands. If a user clicks a specially crafted link within a JavaDoc hover popup, an attacker can execute arbitrary VS Code commands, which can lead to full system compromise in trusted workspaces.

Remediation

Vendor Workaround

To mitigate this issue, users should avoid opening or interacting with untrusted Java projects or files within Red Hat OpenShift Dev Spaces. Exercise caution and refrain from clicking on unfamiliar links presented in JavaDoc hover popups, particularly when working with code from unverified sources. Disabling the `vscode-java` extension when not actively engaged in Java development can further reduce exposure, though this will impact Java-related functionality.

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
CPEs cpe:/a:redhat:openshift_devspaces:3 cpe:/a:redhat:openshift_devspaces:3.29::el9
References
Type Values Removed Values Added
First Time appeared Redhat openshift Dev Spaces
Vendors & Products Redhat openshift Dev Spaces
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description A flaw was found in the vscode-java extension, which provides Java language support for Visual Studio Code. The extension incorrectly trusts all Markdown content in JavaDoc hovers, allowing a malicious Java file to include hidden commands. If a user clicks a specially crafted link within a JavaDoc hover popup, an attacker can execute arbitrary VS Code commands, which can lead to full system compromise in trusted workspaces.
Title Vscode-java: vscode: command injection vulnerability in the javadoc hover provider of the vscode-java extension
First Time appeared Redhat
Redhat openshift Devspaces
Weaknesses CWE-88
CPEs cpe:/a:redhat:openshift_devspaces:3
Vendors & Products Redhat
Redhat openshift Devspaces
References
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
redhat
Published
Updated
Jul 15, 2026, 1:22 AM
Reserved
Jun 22, 2026, 6:09 AM
Status
Modified
Published
Jun 29, 2026, 2:16 PM
Modified
Oct 25, 2026, 9:10 PM
Severity
Important
Public date
Jun 29, 2026, 12:25 PM