CVE-2026-11858

Full vulnerability record from the local CVENow database.

Description

Quanos SCHEMA ST4 on-premises contains a local privilege escalation vulnerability in the Client Update Service. The update service runs as NT AUTHORITY\SYSTEM and exposes a .NET Remoting interface over a named pipe without sufficient access controls or authorization. A local authenticated low-privileged user can connect to the interface and invoke privileged update methods such as Update(). This allows arbitrary file write and delete operations with SYSTEM privileges and can be used to achieve local privilege escalation.

Severity

HIGH

CVSS score

8.4 (v4.0)

Vulnerability status

Deferred

Source identifier

551230f0-3615-47bd-b7cc-93e92e730bbf

Published

2026-06-17 13:19:33.807000

Last modified

2026-10-26 12:10:00.130000

View original CVE JSON

{
  "id": "CVE-2026-11858",
  "sourceIdentifier": "551230f0-3615-47bd-b7cc-93e92e730bbf",
  "published": "2026-06-17T13:19:33.807",
  "lastModified": "2026-10-26T12:10:00.130",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Quanos SCHEMA ST4 on-premises contains a local privilege escalation vulnerability in the Client Update Service. The update service runs as NT AUTHORITY\\SYSTEM and exposes a .NET Remoting interface over a named pipe without sufficient access controls or authorization. A local authenticated low-privileged user can connect to the interface and invoke privileged update methods such as Update(). This allows arbitrary file write and delete operations with SYSTEM privileges and can be used to achieve local privilege escalation."
    },
    {
      "lang": "es",
      "value": "Quanos SCHEMA ST4 local contiene una vulnerabilidad de escalada de privilegios local en el Servicio de Actualización del Cliente. El servicio de actualización se ejecuta como NT AUTHORITY\\SYSTEM y expone una interfaz .NET Remoting a través de una tubería con nombre sin controles de acceso o autorización suficientes. Un usuario local autenticado con bajos privilegios puede conectarse a la interfaz e invocar métodos de actualización privilegiados como Update(). Esto permite operaciones arbitrarias de escritura y eliminación de archivos con privilegios de SYSTEM y puede utilizarse para lograr la escalada de privilegios local."
    }
  ],
  "affected": [
    {
      "source": "551230f0-3615-47bd-b7cc-93e92e730bbf",
      "affectedData": [
        {
          "vendor": "Quanos Solutions GmbH",
          "product": "SCHEMA ST4",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "SCHEMA ST4 on-premises, all versions",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "551230f0-3615-47bd-b7cc-93e92e730bbf",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/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",
          "baseScore": 8.4,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-17T14:56:14.233126Z",
          "id": "CVE-2026-11858",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "551230f0-3615-47bd-b7cc-93e92e730bbf",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-862"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://r.sec-consult.com/quanos",
      "source": "551230f0-3615-47bd-b7cc-93e92e730bbf"
    }
  ]
}