Security Digest · Vulnerability record
CVE-2025-54539: Apache ActiveMQ NMS AMQP Client has a Deserialization of Untrusted Data vulnerability
A Deserialization of Untrusted Data vulnerability exists in the Apache ActiveMQ NMS AMQP Client.
CVSS 9.8 Critical EPSS 2.1% · p81
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 2.1%, percentile 81: FIRST’s model estimates a 2.1% chance of exploitation activity in the next 30 days, higher than 81% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
Apache.NMS.AMQP(NuGet) < 2.4.0, fixed in 2.4.0. Check your lockfile, including transitive dependencies.
What it is
A Deserialization of Untrusted Data vulnerability exists in the Apache ActiveMQ NMS AMQP Client. This issue affects all versions of Apache ActiveMQ NMS AMQP up to and including 2.3.0, when establishing connections to untrusted AMQP servers. Malicious servers could exploit unbounded deserialization logic present in the client to craft responses that may lead to arbitrary code execution on the client side. Although version 2.1.0 introduced a mechanism to restrict deserialization via allow/deny lists, the protection was found to be bypassable under certain conditions. In line with Microsoft’s deprecation of binary serialization in .NET 9, the project is evaluating the removal of .NET binary serialization support from the NMS API entirely in future releases. Mitigation and Recommendations: Users are strongly encouraged to upgrade to version 2.4.0 or later, which resolves the issue. Additionally, projects depending on NMS-AMQP should migrate away from .NET binary serialization as part of a long-term hardening strategy.
From the GitHub advisory
A Deserialization of Untrusted Data vulnerability exists in the Apache ActiveMQ NMS AMQP Client.
This issue affects all versions of Apache ActiveMQ NMS AMQP up to and including 2.3.0, when establishing connections to untrusted AMQP servers. Malicious servers could exploit unbounded deserialization logic present in the client to craft responses that may lead to arbitrary code execution on the client side.
Although version 2.1.0 introduced a mechanism to restrict deserialization via allow/deny lists, the protection was found to be bypassable under certain conditions.
In line with Microsoft’s deprecation of binary serialization in .NET 9, the project is evaluating the removal of .NET binary serialization support from the NMS API entirely in future releases.
Mitigation and Recommendations: Users are strongly encouraged to upgrade to version 2.4.0 or later, which resolves the issue. Additionally, projects depending on NMS-AMQP should migrate away from .NET binary serialization as part of a long-term hardening strategy.
Weakness type: CWE-502.
Product: Apache.NMS.AMQP (NuGet) · Assigned by: apache · Published: 2025-10-16
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| NuGet | Apache.NMS.AMQP | < 2.4.0 | 2.4.0 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| Apache Software Foundation | Apache ActiveMQ NMS AMQP Client | <= 2.3.0 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADP | 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| GitHub | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: unchanged
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 2.09% probability of exploitation activity in the next 30 days; percentile 81.
Timeline
- — CVE record published by apache
- — GitHub-reviewed advisory GHSA-4mjw-xr5x-prpc published (critical)
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vendor and project advisories, patches
- lists.apache.org lists.apache.org
Vulnerability records
- GitHub Advisory GHSA-4mjw-xr5x-prpc github.com
- CVE.org record CVE-2025-54539 cve.org
- NVD entry CVE-2025-54539 nvd.nist.gov
Other references from the CVE record and advisory
- openwall.com openwall.com