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Medium

MQTTX vulnerable to cross-site scripting via improper message payload rendering

Type: advisorySources: OSV

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.

Products
Not specified
Affected versions
Not specified
Fixed versions
Not specified
CVEs
CVE-2025-62413
Confirmed fixed CVEs
Not specified
Updated in this feed
3 Nov 2026, 18:43 UTC · Revision 1

Source evidence

MQTTX vulnerable to cross-site scripting via improper message payload rendering

core-osv · Original source

Published 16 Oct 2025, 18:00 UTC

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.

osv:CVE-2025-62413
Complete source record
{
  "id": "0bfab195746e4aa2d166b3a6aded327d6ec53384bac4ea1ff84fc5f60c7caf0e",
  "url": "https://osv.dev/vulnerability/CVE-2025-62413",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "MQTTX vulnerable to cross-site scripting via improper message payload rendering",
    "summary": "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.",
    "evidence": "osv:CVE-2025-62413",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2025-62413",
      "aliases": [
        "CVE-2025-62413",
        "GHSA-29gf-9r9v-j4m3"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/emqx/mqttx",
              "type": "GIT",
              "events": [
                {
                  "introduced": "bccba93621350c625fb0160a874b4bd3912dc4c8"
                },
                {
                  "fixed": "2963f78a4b3227cdb93597f546a75b75dee1059f"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "= 1.12.0"
                      },
                      {
                        "last_affected": "= 1.12.0"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandaloneSingleVersion"
                  },
                  {
                    "range": [
                      {
                        "fixed": "2963f78a4b3227cdb93597f546a75b75dee1059f"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "= 1.12.0",
            "v1.12.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-62413.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:31.685100586Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/62xxx/CVE-2025-62413.json",
        "https://github.com/emqx/MQTTX/security/advisories/GHSA-29gf-9r9v-j4m3",
        "https://nvd.nist.gov/vuln/detail/CVE-2025-62413",
        "https://github.com/emqx/MQTTX/commit/2963f78a4b3227cdb93597f546a75b75dee1059f"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-79"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/62xxx/CVE-2025-62413.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2025-62413",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 498527,
  "published_at": "2025-10-16T18:00:17.606+00:00"
}