CVE-2025-27533: Apache ActiveMQ Unchecked Buffer Length Can Cause Vulnerability
MODERATECVE-2025-27533 is a MODERATE (CVSS 7.5) unchecked buffer length can cause vulnerability (CWE-789: Memory Allocation with Excessive Size Value) affecting Apache ActiveMQ libraries in the Maven ecosystem. The issue involves unchecked buffer length can cause excessive memory allocation. Remediation is available by upgrading affected packages to version 5.16.8, 5.17.7, 5.18.7, 6.1.6.
CVE-2025-27533 at a Glance
Security Impact
CVSS: 7.5
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).
How to Fix CVE-2025-27533
To remediate this vulnerability, upgrade all affected Apache ActiveMQ dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
<dependency>
<groupId>org.apache.activemq</groupId>
<artifactId>activemq-openwire-legacy</artifactId>
<version>5.16.8</version>
</dependency>
<dependency>
<groupId>org.apache.activemq</groupId>
<artifactId>activemq-client</artifactId>
<version>5.16.8</version>
</dependency>
<dependency>
<groupId>org.apache.activemq</groupId>
<artifactId>activemq-openwire-legacy</artifactId>
<version>5.17.7</version>
</dependency>
<dependency>
<groupId>org.apache.activemq</groupId>
<artifactId>activemq-openwire-legacy</artifactId>
<version>5.18.7</version>
</dependency>
<dependency>
<groupId>org.apache.activemq</groupId>
<artifactId>activemq-openwire-legacy</artifactId>
<version>6.1.6</version>
</dependency>
<dependency>
<groupId>org.apache.activemq</groupId>
<artifactId>activemq-client</artifactId>
<version>5.17.7</version>
</dependency>
<dependency>
<groupId>org.apache.activemq</groupId>
<artifactId>activemq-client</artifactId>
<version>5.18.7</version>
</dependency>
<dependency>
<groupId>org.apache.activemq</groupId>
<artifactId>activemq-client</artifactId>
<version>6.1.6</version>
</dependency>
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
mvn dependency:tree -Dincludes=org.apache.activemq
How to Check if You Are Affected
To determine whether your Java application is affected by CVE-2025-27533, inspect your build dependencies using the Maven Dependency Plugin:
mvn dependency:tree -Dincludes=org.apache.activemq
Analyze the terminal output to locate any version of Apache ActiveMQ in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 5.16.8), your application is affected.
Note: The mvn dependency:tree -Dincludes=org.apache.activemq command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-789: Memory Allocation with Excessive Size Value, where the product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated. In Apache ActiveMQ, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2025-27533 Affected Apache ActiveMQ Versions
8 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
org.apache.activemq:activemq-openwire-legacy
|
Maven |
< 5.16.8
|
5.16.8
|
|
org.apache.activemq:activemq-client
|
Maven |
< 5.16.8
|
5.16.8
|
|
org.apache.activemq:activemq-openwire-legacy
|
Maven |
≥ 5.17.0
< 5.17.7
|
5.17.7
|
|
org.apache.activemq:activemq-openwire-legacy
|
Maven |
≥ 5.18.0
< 5.18.7
|
5.18.7
|
|
org.apache.activemq:activemq-openwire-legacy
|
Maven |
≥ 6.0.0
< 6.1.6
|
6.1.6
|
|
org.apache.activemq:activemq-client
|
Maven |
≥ 5.17.0
< 5.17.7
|
5.17.7
|
|
org.apache.activemq:activemq-client
|
Maven |
≥ 5.18.0
< 5.18.7
|
5.18.7
|
|
org.apache.activemq:activemq-client
|
Maven |
≥ 6.0.0
< 6.1.6
|
6.1.6
|
References
Frequently Asked Questions
What is CVE-2025-27533?
Which Apache ActiveMQ versions are affected?
What version fixes CVE-2025-27533?
Is activemq-openwire-legacy affected?
Is activemq-client affected?
What is the CVSS score of CVE-2025-27533?
What CWE is associated with CVE-2025-27533?
How can I check Maven dependencies for CVE-2025-27533?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-whxr-3p84-rf3c",
"modified" : "2025-11-03T21:33:47Z",
"published" : "2025-05-07T09:31:19Z",
"aliases" : [ "CVE-2025-27533" ],
"summary" : "Apache ActiveMQ: Unchecked buffer length can cause excessive memory allocation",
"details" : "Memory Allocation with Excessive Size Value vulnerability in Apache ActiveMQ.\n\nDuring unmarshalling of OpenWire commands the size value of buffers was not properly validated which could lead to excessive memory allocation and be exploited to cause a denial of service (DoS) by depleting process memory, thereby affecting applications and services that rely on the availability of the ActiveMQ broker when not using mutual TLS connections.\nThis issue affects Apache ActiveMQ: from 6.0.0 before 6.1.6, from 5.18.0 before 5.18.7, from 5.17.0 before 5.17.7, before 5.16.8. ActiveMQ 5.19.0 is not affected.\n\nUsers are recommended to upgrade to version 6.1.6+, 5.19.0+, 5.18.7+, 5.17.7, or 5.16.8 or which fixes the issue.\n\nExisting users may implement mutual TLS to mitigate the risk on affected brokers.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
}, {
"type" : "CVSS_V4",
"score" : "CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/AU:Y/R:A/V:D/RE:M/U:Red"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Maven",
"name" : "org.apache.activemq:activemq-openwire-legacy"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "5.16.8"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Maven",
"name" : "org.apache.activemq:activemq-client"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "5.16.8"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Maven",
"name" : "org.apache.activemq:activemq-openwire-legacy"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.17.0"
}, {
"fixed" : "5.17.7"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Maven",
"name" : "org.apache.activemq:activemq-openwire-legacy"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.18.0"
}, {
"fixed" : "5.18.7"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Maven",
"name" : "org.apache.activemq:activemq-openwire-legacy"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "6.0.0"
}, {
"fixed" : "6.1.6"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Maven",
"name" : "org.apache.activemq:activemq-client"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.17.0"
}, {
"fixed" : "5.17.7"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Maven",
"name" : "org.apache.activemq:activemq-client"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.18.0"
}, {
"fixed" : "5.18.7"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Maven",
"name" : "org.apache.activemq:activemq-client"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "6.0.0"
}, {
"fixed" : "6.1.6"
} ]
} ]
} ],
"references" : [ {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-27533"
}, {
"type" : "WEB",
"url" : "https://github.com/apache/activemq/commit/fc4372b9f0f72b8b5eed917f0019c5cea45c5d06"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/apache/activemq"
}, {
"type" : "WEB",
"url" : "https://issues.apache.org/jira/browse/AMQ-6596"
}, {
"type" : "WEB",
"url" : "https://lists.apache.org/thread/8hcm25vf7mchg4zbbhnlx2lc5bs705hg"
}, {
"type" : "WEB",
"url" : "https://lists.debian.org/debian-lts-announce/2025/06/msg00020.html"
}, {
"type" : "WEB",
"url" : "http://www.openwall.com/lists/oss-security/2025/05/06/1"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-789" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2025-05-07T15:25:41Z",
"nvd_published_at" : "2025-05-07T09:15:18Z"
}
}