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
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Puntuación base: 8.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.55%
- Percentil entre todas las CVEs puntuadas: 44
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1203Exploitation for Client Executionexecution92 % - Impacto principal
T1059Command and Scripting Interpreterexecution88 % - Impacto secundario
T1005Data from Local Systemcollection75 %
Requiere interacción del usuario (UI:R) al hacer clic en enlace de JavaDoc. Ejecución de comandos VS Code arbitrarios en workspace confiable. Acceso a datos del sistema por compromiso total.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-88
- CWE-88
Referencias
- https://access.redhat.com/errata/RHSA-2026:36820
- https://access.redhat.com/security/cve/CVE-2026-12856
- https://bugzilla.redhat.com/show_bug.cgi?id=2491278
- https://github.com/redhat-developer/vscode-java/security/advisories/GHSA-7qv8-6qrw-3crv
- https://access.redhat.com/errata/RHSA-2026:36820
- https://access.redhat.com/security/cve/CVE-2026-12856
- https://bugzilla.redhat.com/show_bug.cgi?id=2491278
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-12856.json
JSON original (NVD)
Mostrar
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