CVE-2026-25551

Seagull Software BarTender 2021 R1 through 12.0.1 contains an insecure deserialization vulnerability that allows low-privileged local users to escalate privileges. The DataServiceSingleton .NET Remoting endpoint is bound to localhost on TCP port 7375 via BtSystem.Service.exe, limiting the attack surface to local access only. The endpoint is configured with BinaryServerFormatterSinkProvider and TypeFilterLevel set to Full. A low-privileged local attacker can send YSoSerial.NET-generated BinaryFormatter payloads to the localhost-bound endpoint to achieve code execution as NT AUTHORITY\\\\SYSTEM. The vulnerability was corrected in BarTender 12.1, released on August 14, 2026. Users should upgrade to BarTender 12.1 or later.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://gist.github.com/VAMorales/dde5b1c0415a8505ccd6fafdb095a618
https://portal.seagullscientific.com/downloads/bartender
https://trust.seagullsoftware.com/?tcuUid=55ed135f-683c-4e9b-a59d-7d4373c0ac7e
https://www.vulncheck.com/advisories/seagull-software-bartender-deserialization-privilege-escalation-via-net-remoting-service

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-04 18:16

Updated : 2026-09-02 17:17

NVD link : CVE-2026-25551

Mitre link : CVE-2026-25551

CVE.ORG link : CVE-2026-25551

JSON object : View

Products Affected

No product.

CWE

CWE-502

Deserialization of Untrusted Data

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El endpoint est\u00e1 configurado con BinaryServerFormatterSinkProvider y TypeFilterLevel establecido en Full. Un atacante local con pocos privilegios puede enviar cargas \u00fatiles de BinaryFormatter generadas por YSoSerial.NET al endpoint enlazado a localhost para lograr la ejecuci\u00f3n de c\u00f3digo como NT AUTHORITY\\\\SYSTEM."}], "lastModified": "2026-09-02T17:17:40.003", "sourceIdentifier": "disclosure@vulncheck.com"}