Deserialization in Apache Activemq Nms Openwire

CVE-2025-29953

Deserialization of Untrusted Data vulnerability in Apache ActiveMQ NMS OpenWire Client. This issue affects Apache ActiveMQ NMS OpenWire Client before 2.1.1 when performing connections to untrusted servers. Such servers could abuse the unbounded deserialization in the client to provide malicious responses that may eventually cause arbitrary code execution on the client. Version 2.1.0 introduced a allow/denylist feature to restrict deserialization, but this feature could be bypassed. The .NET team has deprecated the built-in .NET binary serialization feature starting with .NET 9 and suggests migrating away from binary serialization. The project is considering to follow suit and drop this part of the NMS API altogether. Users are recommended to upgrade to version 2.1.1, which fixes the issue. We also recommend to migrate away from relying on .NET binary serialization as a hardening method for the future.

Vulnerability class: Insecure Deserialization

EPSS: 0.019 (77.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-29953?
CVE-2025-29953 is a critical-severity vulnerability in Apache Activemq Nms Openwire, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2025-04-18.
How severe is CVE-2025-29953?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2025-29953 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.