How severe is CVE-2026-25551?

CVE-2026-25551 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-25551 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-25551?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-25551 have an EU (EUVD) identifier?

Yes. CVE-2026-25551 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-34306.

When was CVE-2026-25551 published?

CVE-2026-25551 was published on 2026-06-04 and last updated on 2026-06-17.

CVE-2026-25551

CVE-2026-25551 is a high-severity vulnerability with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-502.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v4: 8.5
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-34306
Weakness: CWE-502
Published: 2026-06-04
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-25551?: CVE-2026-25551 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-25551 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-25551?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-25551 have an EU (EUVD) identifier?: Yes. CVE-2026-25551 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-34306.
When was CVE-2026-25551 published?: CVE-2026-25551 was published on 2026-06-04 and last updated on 2026-06-17.

References

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