MQTTX desktop through 1.13.3 contains a stored cross-site scripting vulnerability that allows attackers to inject
Source GCVE Database
Not known to be exploited · CVSS 5.3 Medium.
Data as of 11 Nov 2026, 04:37 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 5.3 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 6.1 |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 11 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 10 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| emqxMQTTX | Affected
| Fixed in– |
GitHubMQTTXpkg:github/MQTTXOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Until a fix is available, users should exercise caution when interacting with untrusted MQTT brokers or topics. Avoid hovering over suspicious topic names or JSON tree nodes. Monitor official MQTTX channels for updates and apply patches promptly once released.
Description
MQTTX desktop versions up to 1.13.3 have a stored cross-site scripting (XSS) vulnerability. This flaw allows attackers who control an MQTT broker or publish to subscribed topics to inject malicious scripts via MQTT topic names or payloads. These scripts execute in the Electron renderer process with nodeIntegration enabled when victims hover over certain UI elements, such as Topic Tree or JSON tree nodes. The vulnerability has a CVSS score of 6.1, indicating medium severity.
References
- nvd.nist.gov/vuln/detail/CVE-2026-126495 (opens in a new tab)
- github.com/emqx/MQTTX/issues/2180 (opens in a new tab)
- github.com/emqx/MQTTX (opens in a new tab)
- github.com/emqx/MQTTX/blob/v1.13.3/src/background.ts (opens in a new tab)
- github.com/emqx/MQTTX/blob/v1.13.3/src/widgets/JSONViewer.vue (opens in a new tab)
- github.com/emqx/MQTTX/blob/v1.13.3/src/widgets/TreeView.vue (opens in a new tab)
- vulncheck.com/advisories/mqttx-through-1.13.3-stored-xss-via-topic-tree-and-json-tree-tooltips (opens in a new tab)