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Vulnerability record · CVE-2026-21665 · published 23 February 2026

CVE-2026-21665: Deserialization of untrusted data vulnerability

The Print Service component of Fiserv Originate Loans Peripherals (formerly Velocity Services) in unsupported version 2021.2.4 (build 4.7.3155.0011) uses deprecated .NET Remoting TCP channels that allow unsafe deserialization of untrusted data. When these services are exposed to an untrusted network in a client-managed deployment, an unauthenticated attacker can achieve remote code execution. Version 2021.2.4 is no longer supported by Fiserv. Customers should upgrade to a currently supported release (2025.1 or later) and ensure that .NET Remoting service ports are not exposed beyond trusted network boundaries. This CVE documents behavior observed in a client-hosted deployment running an unsupported legacy version of Originate Loans Peripherals with .NET Remoting ports exposed to an untrusted network. This is not a default or supported configuration. Customers running legacy versions should upgrade to a currently supported release and ensure .NET Remoting ports are restricted to trusted network segments. The finding does not apply to Fiserv-hosted environments.

7.7 CVSS 4.0 High EPSS 0.46% · top 62.4% CWE-502 · Deserialization of untrusted data Deferred
7.7CVSS 4.0 base score
0.46%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
1References
17 Jun 2026Last modified by NVD

Description

The Print Service component of Fiserv Originate Loans Peripherals (formerly Velocity Services) in unsupported version 2021.2.4 (build 4.7.3155.0011) uses deprecated .NET Remoting TCP channels that allow unsafe deserialization of untrusted data. When these services are exposed to an untrusted network in a client-managed deployment, an unauthenticated attacker can achieve remote code execution. Version 2021.2.4 is no longer supported by Fiserv. Customers should upgrade to a currently supported release (2025.1 or later) and ensure that .NET Remoting service ports are not exposed beyond trusted network boundaries. This CVE documents behavior observed in a client-hosted deployment running an unsupported legacy version of Originate Loans Peripherals with .NET Remoting ports exposed to an untrusted network. This is not a default or supported configuration. Customers running legacy versions should upgrade to a currently supported release and ensure .NET Remoting ports are restricted to trusted network segments. The finding does not apply to Fiserv-hosted environments.

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/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:

References

LinkTags
https://learn.microsoft.com/en-us/dotnet/core/compatibility/core-libraries/5.0/remoting-apis-obsolete

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Source: NIST National Vulnerability Database (record CVE-2026-21665), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.