6.1
MEDIUM CVSS 3.1
CVE-2026-126495
MQTTX through 1.13.3 Stored XSS via Topic Tree and JSON Tree Tooltips
Description

MQTTX desktop through 1.13.3 contains a stored cross-site scripting vulnerability that allows attackers to inject script by publishing malicious MQTT topic names or payloads rendered unescaped in tooltips. Attackers controlling a broker or publishing to subscribed topics can execute script in the Electron renderer, which has nodeIntegration enabled, when victims hover Topic Tree or JSON tree nodes.

INFO

Published Date :

Nov. 11, 2026, 1:17 a.m.

Last Modified :

Nov. 11, 2026, 1:17 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-126495 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 MEDIUM [email protected]
Solution
Update MQTTX desktop to a version later than 1.13.3 to fix the stored XSS vulnerability.
  • Update MQTTX desktop to the latest version.
  • Avoid using unescaped data in tooltips.
  • Disable nodeIntegration in Electron renderers.
  • Sanitize MQTT topic names and payloads.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-126495 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-126495 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-126495 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-126495 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Nov. 11, 2026

    Action Type Old Value New Value
    Added Description MQTTX desktop through 1.13.3 contains a stored cross-site scripting vulnerability that allows attackers to inject script by publishing malicious MQTT topic names or payloads rendered unescaped in tooltips. Attackers controlling a broker or publishing to subscribed topics can execute script in the Electron renderer, which has nodeIntegration enabled, when victims hover Topic Tree or JSON tree nodes.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
    Added CWE CWE-79
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/126xxx/CVE-2026-126495.json">CVE-2026-126495</a>
    Added Reference https://github.com/emqx/MQTTX
    Added Reference https://github.com/emqx/MQTTX/blob/v1.13.3/src/background.ts#L276-L283
    Added Reference https://github.com/emqx/MQTTX/blob/v1.13.3/src/widgets/JSONViewer.vue#L175-L184
    Added Reference https://github.com/emqx/MQTTX/blob/v1.13.3/src/widgets/TreeView.vue#L195-L226
    Added Reference https://github.com/emqx/MQTTX/issues/2180
    Added Reference https://www.vulncheck.com/advisories/mqttx-through-1.13.3-stored-xss-via-topic-tree-and-json-tree-tooltips
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.