High 7.8Published Jun 4, 2026

CVE-2026-25551Seagull Software BarTender Deserialization Privilege Escalation via .NET Remoting Service

Updated under an hour ago (Oct 28, 2026, 4:50 AM ET)

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It affects Seagull Software, LLC. BarTender 2021. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Seagull Software, LLC. BarTender 2021

Exploited in the last 30 days

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: 7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-502
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Awaiting Analysis
Record last updated: Sep 2, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Seagull Software, LLC. BarTender 2021 seagull_software:bartender_2021 (from the name)	from R1 through 12.0.1	CNA record

References

References

https://trust.seagullsoftware.com/?tcuUid=55ed135f-683c-4e9b-a59d-7d4373c0ac7e	vendor-advisory, patch
https://gist.github.com/VAMorales/dde5b1c0415a8505ccd6fafdb095a618	technical-description, exploit
https://portal.seagullscientific.com/downloads/bartender	product
https://www.vulncheck.com/advisories/seagull-software-bartender-deserialization-privilege-escalation-via-net-remoting-service	third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.