CVE-2020-5231
In Opencast before 7.6 and 8.1, users with the role ROLE_COURSE_ADMIN can use the user-utils endpoint to create new users not including the role ROLE_ADMIN. ROLE_COURSE_ADMIN is a non-standard role in Opencast which is referenced neither in the documentation nor in any code (except for tests) but only in the security configuration. From the name – implying an admin for a specific course – users would never expect that this role allows user creation. This issue is fixed in 7.6 and 8.1 which both ship a new default security configuration.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
- Puntuación base: 6.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.63%
- Percentil entre todas las CVEs puntuadas: 48
- 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.
- Impacto principal
T1078.001Default Accountsstealth · persistence · privilege escalation · initial access - Impacto secundario
T1136Create Accountpersistence
Fuente: mapeo oficial MITRE CTID (CVE → ATT&CK).
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-285
- CWE-276
Referencias
- https://github.com/opencast/opencast/commit/72fad0031d8a82c860e2bde0b27570c5042320ee
- https://github.com/opencast/opencast/security/advisories/GHSA-94qw-r73x-j7hg
- https://github.com/opencast/opencast/commit/72fad0031d8a82c860e2bde0b27570c5042320ee
- https://github.com/opencast/opencast/security/advisories/GHSA-94qw-r73x-j7hg
JSON original (NVD)
Mostrar
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"value": "In Opencast before 7.6 and 8.1, users with the role ROLE_COURSE_ADMIN can use the user-utils endpoint to create new users not including the role ROLE_ADMIN. ROLE_COURSE_ADMIN is a non-standard role in Opencast which is referenced neither in the documentation nor in any code (except for tests) but only in the security configuration. From the name – implying an admin for a specific course – users would never expect that this role allows user creation. This issue is fixed in 7.6 and 8.1 which both ship a new default security configuration."
},
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}
],
"lastModified": "2026-06-17T03:21:04.517",
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