Skip to main content
HIGH

CVE-2025-27533

CVSS v3

7.5

HIGH

EPSS Score

8.7 %

exploit probability, as of 2026-09-25

CISA KEV

No

known exploited

Exploitation

—

SSVC status

Description

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.

Technical details

Published
2025-05-07
Exploit-DB
EDB-52288

Frequently asked questions

What is CVE-2025-27533?

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.

Is CVE-2025-27533 actively exploited?

Active exploitation of CVE-2025-27533 has not been confirmed. Its EPSS score was 8.7% on 2026-09-25, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2025-27533?

CVE-2025-27533 has a CVSS v3 base score of 7.5 (HIGH severity).

Is CVE-2025-27533 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.

Check an IPSearch CVEsSIEM & TIP integrations

No credit card required · 500 free checks/month · Free API key

Other 2025 vulnerabilities worth triaging

Ranked by exploit probability (EPSS).

Back to CVE Database