Apache ActiveMQ up to 5.16.7/5.17.6/5.18.6/6.1.5 OpenWire Command memory allocation

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.79

Summaryinfo

A vulnerability was found in Apache ActiveMQ up to 5.16.7/5.17.6/5.18.6/6.1.5. It has been classified as problematic. Affected is an unknown function of the component OpenWire Command Handler. This manipulation causes memory allocation. The identification of this vulnerability is CVE-2025-27533. Furthermore, there is an exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability has been found in Apache ActiveMQ up to 5.16.7/5.17.6/5.18.6/6.1.5 and classified as problematic. Affected by this vulnerability is an unknown code block of the component OpenWire Command Handler. The manipulation with an unknown input leads to a memory allocation vulnerability. The CWE definition for the vulnerability is CWE-789. 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. As an impact it is known to affect availability. The summary by CVE is:

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.

The advisory is shared at lists.apache.org. This vulnerability is known as CVE-2025-27533 since 02/28/2025. The exploitation appears to be easy. Technical details are unknown but a public exploit is available.

It is possible to download the exploit at exploit-db.com. It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 235662 (Apache ActiveMQ 5.16.x < 5.16.8 / 5.17.x < 5.17.7 / 5.18.x < 5.18.7 / 6.x < 6.1.6 DoS (CVE-2025-27533)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.16.8, 5.17.7, 5.18.7 or 6.1.6 eliminates this vulnerability.

The vulnerability is also documented in the databases at Exploit-DB (52288), Tenable (235662) and CERT Bund (WID-SEC-2026-0783). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • IBM QRadar SIEM

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

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CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.3

VulDB Base Score: 3.5
VulDB Temp Score: 3.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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Exploitinginfo

Class: Memory allocation
CWE: CWE-789 / CWE-400 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 235662
Nessus Name: Apache ActiveMQ 5.16.x < 5.16.8 / 5.17.x < 5.17.7 / 5.18.x < 5.18.7 / 6.x < 6.1.6 DoS (CVE-2025-27533)

Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: ActiveMQ 5.16.8/5.17.7/5.18.7/6.1.6

Timelineinfo

02/28/2025 🔍
05/06/2025 +66 days 🔍
05/06/2025 +0 days 🔍
03/19/2026 +317 days 🔍

Sourcesinfo

Vendor: apache.org

Advisory: lists.apache.org
Status: Confirmed

CVE: CVE-2025-27533 (🔍)
GCVE (CVE): GCVE-0-2025-27533
GCVE (VulDB): GCVE-100-307669
CERT Bund: WID-SEC-2026-0783 - IBM QRadar SIEM: Mehrere Schwachstellen

scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 05/06/2025 21:15
Updated: 03/19/2026 11:36
Changes: 05/06/2025 21:15 (54), 05/10/2025 10:18 (2), 05/12/2025 07:44 (11), 07/18/2025 17:12 (30), 03/19/2026 11:36 (7)
Complete: 🔍
Cache ID: 216::103

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