CVE-2026-21665
Unsafe Deserialization in Fiserv Print Service Enables RCE
Publication date: 2026-02-23
Last updated on: 2026-02-25
Assigner: HackerOne
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| fiserv | originate_loans_peripherals | to 2025.1 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-502 | The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid. |
Attack-Flow Graph
AI Powered Q&A
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, customers should upgrade from the unsupported version 2021.2.4 of Fiserv Originate Loans Peripherals to a currently supported release, version 2025.1 or later.
Additionally, ensure that .NET Remoting service ports are not exposed beyond trusted network boundaries by restricting these ports to trusted network segments.
Note that this vulnerability applies only to client-hosted deployments with exposed .NET Remoting ports and does not affect Fiserv-hosted environments.
Can you explain this vulnerability to me?
The vulnerability exists in the Print Service component of Fiserv Originate Loans Peripherals version 2021.2.4, which uses deprecated .NET Remoting TCP channels. These channels allow unsafe deserialization of untrusted data, meaning that when the service ports are exposed to an untrusted network, an unauthenticated attacker can exploit this to execute remote code on the system.
This issue occurs specifically in client-managed deployments where the .NET Remoting service ports are exposed beyond trusted network boundaries. The affected version is no longer supported, and the vulnerability does not apply to Fiserv-hosted environments.
How can this vulnerability impact me? :
If you are running the unsupported version 2021.2.4 of Fiserv Originate Loans Peripherals with exposed .NET Remoting TCP ports, an unauthenticated attacker could remotely execute arbitrary code on your system. This could lead to full compromise of the affected system, unauthorized access, data theft, or disruption of services.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know