CVE-2026-12856

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:36820
https://access.redhat.com/security/cve/CVE-2026-12856	Mitigation Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2491278	Issue Tracking Vendor Advisory
https://github.com/redhat-developer/vscode-java/security/advisories/GHSA-7qv8-6qrw-3crv	Broken Link
https://access.redhat.com/errata/RHSA-2026:36820
https://access.redhat.com/security/cve/CVE-2026-12856	Mitigation Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2491278	Issue Tracking Vendor Advisory
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-12856.json	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:redhat:openshift_dev_spaces:-:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-06-29 14:16

Updated : 2026-07-15 02:18

NVD link : CVE-2026-12856

Mitre link : CVE-2026-12856

CVE.ORG link : CVE-2026-12856

JSON object : View

Products Affected

redhat

openshift_dev_spaces

CWE

CWE-88

Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')

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