CVE-2025-62413 MQTTX vulnerable to cross-site scripting via improper message payload rendering
Attackers can execute arbitrary scripts in the MQTTX UI via malicious message payloads, potentially stealing credentials or triggering actions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2025-62413?
CVE-2025-62413 is a medium-severity cross-site scripting vulnerability in emqx MQTTX, published on 16 Oct 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-79
Which versions are affected by CVE-2025-62413?
How do I fix CVE-2025-62413?
No fix has been published for CVE-2025-62413 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2025-62413 being exploited?
There is no known exploitation of CVE-2025-62413 in the wild and no public exploit code.
Sources
Also known as GHSA-29gf-9r9v-j4m3.