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CVE-2025-27533 is a denial-of-service vulnerability in Apache ActiveMQ caused by improper validation of buffer size values during unmarshalling of OpenWire commands. A crafted OpenWire message can supply an excessive size value that is accepted during buffer handling, leading the broker process to allocate an excessively large amount of memory. This can exhaust available process memory and disrupt broker availability. The issue affects Apache ActiveMQ 6.0.0 before 6.1.6, 5.18.0 before 5.18.7, 5.17.0 before 5.17.7, and versions before 5.16.8; ActiveMQ 5.19.0 is not affected.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).
This repository contains a Python proof-of-concept (PoC) exploit for CVE-2025-27533, a Denial of Service (DoS) vulnerability in Apache ActiveMQ. The main file, 'CVE-2025-27533_Exploit.py', is a standalone script that allows an attacker to send a large number of custom-crafted OpenWire protocol packets with oversized buffers to a target ActiveMQ server (default port 61616). The script is configurable via command-line arguments for the target host, port, number of packets, and buffer sizes. It includes features for checking the availability of both the OpenWire port and the web admin interface (default port 8161) before and after the attack. The exploit's goal is to exhaust the JVM heap memory of the target, potentially crashing the ActiveMQ service and causing a denial of service. The repository also includes a README with usage instructions, a LICENSE file, and a .gitignore. No weaponized or post-exploitation payloads are present; the exploit is focused solely on causing a DoS condition.
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Cross-references every affected SKU, including bundled OEM variants.
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