CVE-2021-26084
In affected versions of Confluence Server and Data Center, an OGNL injection vulnerability exists that would allow an unauthenticated attacker to execute arbitrary code on a Confluence Server or Data Center instance. The affected versions are before version 6.13.23, from version 6.14.0 before 7.4.11, from version 7.5.0 before 7.11.6, and from version 7.12.0 before 7.12.5.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 9.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 100%
- Percentil entre todas las CVEs puntuadas: 100
- Fecha de la puntuación: 29/9/2026
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).
CISA KEV — explotada activamente
- Añadida al catálogo: 3/11/2021
- Plazo de remediación: 17/11/2021
- Uso conocido en ransomware: Known
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access95 % - Impacto principal
T1059.001PowerShellexecution95 % - Impacto secundario
T1486Data Encrypted for Impactimpact85 % - Impacto secundario
T1565.001Stored Data Manipulationimpact75 %
OGNL injection en servicio web sin autenticación (AV:N/PR:N) permite ejecución arbitraria de código. Confirmado por ransomware en KEV, implicando encriptación y manipulación de datos.
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 (2)
CWE
- CWE-917
- CWE-917
Referencias
- http://packetstormsecurity.com/files/167449/Atlassian-Confluence-Namespace-OGNL-Injection.html
- https://jira.atlassian.com/browse/CONFSERVER-67940
- http://packetstormsecurity.com/files/167449/Atlassian-Confluence-Namespace-OGNL-Injection.html
- https://jira.atlassian.com/browse/CONFSERVER-67940
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-26084
JSON original (NVD)
Mostrar
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