Vulnerability in Red Hat Openshift Dev Spaces
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.005 (43.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 43.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2026-12856 (Mitigation, vdb-entry, Vendor Advisory)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking, Issue Tracking, Vendor Advisory)
- github.com/redhat-developer/vscode-java/security/advisories/GHSA-7qv8-6qrw-3crv (Broken Link)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c (Vendor Advisory)
- access.redhat.com/errata/RHSA-2026:36820 (vendor-advisory)
Frequently asked questions
- What is CVE-2026-12856?
- CVE-2026-12856 is a high-severity vulnerability in Red Hat Openshift Dev Spaces, classified under Argument Injection. CVSS score: 8.8/10. Published 2026-06-29.
- How severe is CVE-2026-12856?
- High severity. CVSS v3 base score is 8.8 out of 10.