SECUFOCUSNOW
Home›CVE index›CVE-2026-25551
Review reviewHigh

CVE-2026-25551

Seagull Software, LLC. BarTender 2021

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.

CVSS
8.5
EPSS
0.13%
3.04% percentile
CISA KEV
Not listed
Published
2026.06.05
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.13%
Technical severityCVSS 8.5

Vulnerability overview

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.

Affected product and versions

Product
Seagull Software, LLC. BarTender 2021
Affected versions
>= R1 <= 12.0.1
Fixed versions
No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Seagull Software, LLC. BarTender 2021 and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/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
CWE
CWE-502