// For flags

CVE-2025-27533

Apache ActiveMQ: Unchecked buffer length can cause excessive memory allocation

Severity Score

6.9
*CVSS v4

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

3
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

Memory Allocation with Excessive Size Value vulnerability in Apache ActiveMQ. During 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.
This 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. Users 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. Existing users may implement mutual TLS to mitigate the risk on affected brokers.

Memory Allocation with Excessive Size Value vulnerability in Apache ActiveMQ. During 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. This 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. Users 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. Existing users may implement mutual TLS to mitigate the risk on affected brokers.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Attack Requirements
Present
Privileges Required
High
User Interaction
None
System
Vulnerable | Subsequent
Confidentiality
None
None
Integrity
None
None
Availability
High
High
Attack Vector
Network
Attack Complexity
Low
Attack Requirements
Present
Privileges Required
High
User Interaction
None
System
Vulnerable | Subsequent
Confidentiality
None
None
Integrity
None
None
Availability
High
High
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2025-02-28 CVE Reserved
  • 2025-05-07 CVE Published
  • 2025-05-07 CVE Updated
  • 2025-05-09 First Exploit
  • 2025-05-15 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-789: Memory Allocation with Excessive Size Value
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Apache Software Foundation
Search vendor "Apache Software Foundation"
 Apache ActiveMQ
Search vendor "Apache Software Foundation" for product "Apache ActiveMQ"
 >= 6.0.0 < 6.1.6
Search vendor "Apache Software Foundation" for product "Apache ActiveMQ" and version " >= 6.0.0 < 6.1.6"
en
Affected
Apache Software Foundation
Search vendor "Apache Software Foundation"
 Apache ActiveMQ
Search vendor "Apache Software Foundation" for product "Apache ActiveMQ"
 >= 5.18.0 < 5.18.7
Search vendor "Apache Software Foundation" for product "Apache ActiveMQ" and version " >= 5.18.0 < 5.18.7"
en
Affected
Apache Software Foundation
Search vendor "Apache Software Foundation"
 Apache ActiveMQ
Search vendor "Apache Software Foundation" for product "Apache ActiveMQ"
 >= 5.17.0 < 5.17.7
Search vendor "Apache Software Foundation" for product "Apache ActiveMQ" and version " >= 5.17.0 < 5.17.7"
en
Affected
Apache Software Foundation
Search vendor "Apache Software Foundation"
 Apache ActiveMQ
Search vendor "Apache Software Foundation" for product "Apache ActiveMQ"
 >= 5.16.0 < 5.16.8
Search vendor "Apache Software Foundation" for product "Apache ActiveMQ" and version " >= 5.16.0 < 5.16.8"
en
Affected