CVE-2026-26221

Estado: AplazadaCrítica (9.3)—

Hyland OnBase contains an unauthenticated .NET Remoting exposure in the OnBase Workflow Timer Service (Hyland.Core.Workflow.NTService.exe). An attacker who can reach the service can send crafted .NET Remoting requests to default HTTP channel endpoints on TCP/8900 (e.g., TimerServiceAPI.rem and TimerServiceEvents.rem for Workflow) to trigger unsafe object unmarshalling, enabling arbitrary file read/write. By writing attacker-controlled content into web-accessible locations or chaining with other OnBase features, this can lead to remote code execution. The same primitive can be abused by supplying a UNC path to coerce outbound NTLM authentication (SMB coercion) to an attacker-controlled host.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:N/AC:L/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: 9.3

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 1.44%
Percentil entre todas las CVEs puntuadas: 72
Fecha de la puntuación: 5/10/2026

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.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access92 %
Impacto principalT1059 Command and Scripting Interpreterexecution88 %
Impacto secundarioT1005 Data from Local Systemcollection85 %

Servicio .NET Remoting no autenticado en red (AV:N, PR:N, UI:N) expone deserialización insegura (CWE-502) permitiendo ejecución de código remoto y acceso a archivos. Vector CVSS crítico confirma explotación remota sin privilegios previos.

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

Privileged Account Management Vulnerability Scanning Restrict Web-Based Content Network Segmentation Limit Software Installation Limit Access to Resource Over Network

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Hyland — Onbase^AI

CWE

CWE-502

Referencias

JSON original (NVD)

Mostrar

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          "options": [
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  "published": "2026-02-13T16:16:11.683",
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      "source": "disclosure@vulncheck.com"
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    {
      "url": "https://www.hyland.com/en/solutions/products/onbase",
      "source": "disclosure@vulncheck.com"
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    {
      "url": "https://www.vulncheck.com/advisories/hyland-onbase-timer-services-unauthenticated-net-remoting-rce",
      "source": "disclosure@vulncheck.com"
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      "lang": "en",
      "value": "Hyland OnBase contains an unauthenticated .NET Remoting exposure in the OnBase Workflow Timer Service (Hyland.Core.Workflow.NTService.exe). An attacker who can reach the service can send crafted .NET Remoting requests to default HTTP channel endpoints on TCP/8900 (e.g., TimerServiceAPI.rem and TimerServiceEvents.rem for Workflow) to trigger unsafe object unmarshalling, enabling arbitrary file read/write. By writing attacker-controlled content into web-accessible locations or chaining with other OnBase features, this can lead to remote code execution. The same primitive can be abused by supplying a UNC path to coerce outbound NTLM authentication (SMB coercion) to an attacker-controlled host."
    },
    {
      "lang": "es",
      "value": "Hyland OnBase contiene una exposición de .NET Remoting sin autenticación en el Servicio de Temporizador de Flujo de Trabajo de OnBase (Hyland.Core.Workflow.NTService.exe). Un atacante que puede alcanzar el servicio puede enviar solicitudes de .NET Remoting manipuladas a los puntos finales de canal HTTP predeterminados en TCP/8900 (p. ej., TimerServiceAPI.rem y TimerServiceEvents.rem para Flujo de Trabajo) para activar la deserialización insegura de objetos, lo que permite la lectura/escritura arbitraria de archivos. Al escribir contenido controlado por el atacante en ubicaciones accesibles por la web o encadenando con otras características de OnBase, esto puede llevar a la ejecución remota de código. La misma primitiva puede ser abusada al proporcionar una ruta UNC para forzar la autenticación NTLM saliente (coerción SMB) a un host controlado por el atacante."
    }
  ],
  "lastModified": "2026-06-17T10:25:58.037",
  "sourceIdentifier": "disclosure@vulncheck.com"
}