CVE-2026-11857: CWE-502 Deserialization of untrusted data in Quanos Solutions GmbH SCHEMA ST4
Quanos SCHEMA ST4 on-premises has a local privilege escalation vulnerability in its Client Update Service due to insecure deserialization in the .NET Remoting service. An authenticated local attacker can exploit this by sending crafted serialized objects via a named pipe to execute arbitrary code with SYSTEM privileges. Network exploitation is not possible; local access with authentication is required.
AI Analysis
Technical Summary
CVE-2026-11857 describes a vulnerability in Quanos SCHEMA ST4 on-premises where the Client Update Service uses .NET Remoting with TypeFilterLevel.Full and listens on local named pipes. This insecure deserialization allows a local authenticated attacker to connect to the named pipe endpoint and send malicious serialized objects, resulting in arbitrary code execution with NT AUTHORITY\SYSTEM privileges. The attack vector is limited to local authenticated users; remote network exploitation is not feasible.
Potential Impact
Successful exploitation grants an attacker arbitrary code execution with SYSTEM-level privileges on the affected host. This enables full control over the system, including the ability to modify or delete data, install software, and alter system configurations. However, exploitation requires local authenticated access, limiting the attack scope to users with existing credentials on the machine.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict local authenticated user access to trusted personnel only. Monitor for unusual activity related to the Client Update Service and .NET Remoting endpoints. Do not expose the named pipe interfaces beyond necessary local users.
CVE-2026-11857: CWE-502 Deserialization of untrusted data in Quanos Solutions GmbH SCHEMA ST4
Description
Quanos SCHEMA ST4 on-premises has a local privilege escalation vulnerability in its Client Update Service due to insecure deserialization in the .NET Remoting service. An authenticated local attacker can exploit this by sending crafted serialized objects via a named pipe to execute arbitrary code with SYSTEM privileges. Network exploitation is not possible; local access with authentication is required.
CVSS v4.0
Score 8.4high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-11857 describes a vulnerability in Quanos SCHEMA ST4 on-premises where the Client Update Service uses .NET Remoting with TypeFilterLevel.Full and listens on local named pipes. This insecure deserialization allows a local authenticated attacker to connect to the named pipe endpoint and send malicious serialized objects, resulting in arbitrary code execution with NT AUTHORITY\SYSTEM privileges. The attack vector is limited to local authenticated users; remote network exploitation is not feasible.
Potential Impact
Successful exploitation grants an attacker arbitrary code execution with SYSTEM-level privileges on the affected host. This enables full control over the system, including the ability to modify or delete data, install software, and alter system configurations. However, exploitation requires local authenticated access, limiting the attack scope to users with existing credentials on the machine.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict local authenticated user access to trusted personnel only. Monitor for unusual activity related to the Client Update Service and .NET Remoting endpoints. Do not expose the named pipe interfaces beyond necessary local users.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- SEC-VLab
- Date Reserved
- 2026-06-10T09:08:22.916Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a32971a0b89be68884c1f99
Added to database: 6/17/2026, 12:46:18 PM
Last enriched: 6/17/2026, 1:00:12 PM
Last updated: 6/17/2026, 1:51:11 PM
Views: 3
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