emqx MQTTX 1.12.0 MQTT cross site scripting

Summaryinfo

A vulnerability was found in emqx MQTTX 1.12.0. It has been rated as problematic. This vulnerability affects unknown code of the component MQTT Handler. Performing a manipulation results in cross site scripting. This vulnerability is identified as CVE-2025-62413. The attack can be initiated remotely. There is not any exploit available. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability, which was classified as problematic, was found in emqx MQTTX 1.12.0. This affects an unknown function of the component MQTT Handler. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. The summary by CVE is:

MQTTX is an MQTT 5.0 desktop client and MQTT testing tool. A Cross-Site Scripting (XSS) vulnerability was introduced in MQTTX v1.12.0 due to improper handling of MQTT message payload rendering. Malicious payloads containing HTML or JavaScript could be rendered directly in the MQTTX message viewer. If exploited, this could allow attackers to execute arbitrary scripts in the context of the application UI — for example, attempting to access MQTT connection credentials or trigger unintended actions through script injection. This vulnerability is especially relevant when MQTTX is used with brokers in untrusted or multi-tenant environments, where message content cannot be fully controlled. This vulnerability is fixed in 1.12.1.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2025-62413 since 10/13/2025. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

Applying the patch 2963f78a4b3227cdb93597f546a75b75dee1059f is able to eliminate this problem. The bugfix is ready for download at github.com.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• emqx

Name

• MQTTX

Version

• 1.12.0

License

• open-source

Website

• Product: https://github.com/emqx/MQTTX/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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