CVE-2026-27760
OpenCATS prior to commit 3002a29 contains a PHP code injection vulnerability in the installer AJAX endpoint that allows unauthenticated attackers to execute arbitrary code by injecting PHP statements into the databaseConnectivity action parameter. Attackers can break out of the define() string context in config.php using a single quote and statement separator to inject malicious PHP code that persists and executes on every subsequent page load when the installation wizard remains incomplete.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Puntuación base: 9.2
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 3.43%
- Percentil entre todas las CVEs puntuadas: 89
- 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
T1190Exploit Public-Facing Applicationinitial access95 % - Impacto principal
T1059Command and Scripting Interpreterexecution90 %
Inyección PHP en endpoint AJAX sin autenticación accesible vía red. CWE-94 y AV:N/PR:N confirman T1190. Ejecución de código arbitrario (T1059) como impacto directo.
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)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-94
Referencias
- https://chocapikk.com/posts/2026/opencats-installer-rce/
- https://github.com/opencats/OpenCATS/blob/46e4727/lib/CATSUtility.php#L142-L172
- https://github.com/opencats/OpenCATS/blob/46e4727/modules/install/ajax/ui.php#L130
- https://github.com/opencats/OpenCATS/commit/3002a29f4c3cada1aa2c4f3d4ae4e189906606b6
- https://github.com/opencats/OpenCATS/pull/706
- https://www.vulncheck.com/advisories/opencats-php-code-injection-via-installer-ajax-endpoint
JSON original (NVD)
Mostrar
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