Sign in
Deutsch English Español Polski
Medium

Mautic vulnerable to reflected XSS in lead:addLeadTags - Quick Add

  • Disclosed: 03.09.2025
  • Updated: 11.10.2026 10:22

Summary

A Cross-Site Scripting (XSS) vulnerability allows an attacker to execute arbitrary JavaScript in the context of another user’s session. This occurs because user-supplied input is reflected back in the server’s response without proper sanitization or escaping, potentially enabling malicious actions such as session hijacking, credential theft, or unauthorized actions in the application.

Details

The vulnerability resides in the “Tags” input field on the /s/ajax?action=lead:addLeadTags endpoint. Although the server applies sanitization before storing the data or returning it later, the payload is executed immediately in the victim’s browser upon reflection, allowing an attacker to run arbitrary JavaScript in the user’s session.

Impact

A Reflected XSS attack can have a significant impact, allowing attackers to steal sensitive user data like cookies, redirect users to malicious websites, manipulate the web page content, and essentially take control of a user's session within an application by executing malicious JavaScript code within the victim's browser, even if the server-side code is secure; essentially enabling them to perform actions as if they were the logged-in user.

References

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Composer package mautic/core >= 4.4.0, < 4.4.17, >= 5.0.0-alpha, < 5.2.8, >= 6.0.0-alpha, < 6.0.5 4.4.17, 5.2.8, 6.0.5

References

CVSS score -
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
Weakness (CWE)
CWE-79
Platform
Composer
Package
mautic/core
Disclosed
03.09.2025
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-9v8p-m85m-f7mm - CC BY 4.0

Vulnerability history: mautic/core

All published vulnerabilities of this package (Composer package), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (57) in the archive
Total entries
57
First → latest
01.2021 07.2026
Without a fix
1
Exploited in attacks
0

Severity breakdown

  • Critical 9
  • High 17
  • Medium 29
  • Low 2

Disclosures per year

Severity:
  1. Mautic has Stored Cross-Site Scripting (XSS) in Projects Component
    High · 7.6 CVE-2026-9809 >= 7.0.0, < 7.1.2 7.1.2
  2. Mautic has an Authorization Bypass in API v2 Endpoints
    High · 7.1 CVE-2026-9808 >= 7.0.0, < 7.1.2 7.1.2
  3. Mautic vulnerable to Path Traversal via Campaign Import
    Critical · 9.9 CVE-2026-9559 >= 7.0.0, < 7.1.2 7.1.2
  4. Mautic has Server-Side Template Injection (SSTI) in Theme Templates
    Critical · 9.9 CVE-2026-9558 >= 1.3.0, >= 5.0.0, < 5.2.11, >= 6.0.0, < 6.0.9, >= 7.0.0, < 7.1.2 5.2.11, 6.0.9, 7.1.2
  5. Mautic has SQL Injection in API Contact Filtering
    High · 7.1 CVE-2026-4776 >= 2.6.0, <= 4.4.13, >= 5.0.0, < 5.2.11, >= 6.0.0, < 6.0.9, >= 7.0.0, < 7.1.2 5.2.11, 6.0.9, 7.1.2
  6. Mautic is Vulnerable to SQL Injection through Contact Activity API Sorting
    High · 7.6 CVE-2026-3105 >= 2.10.0, < 5.2.10, >= 6.0.0-alpha, < 6.0.8, >= 7.0.0-alpha, < 7.0.1 5.2.10, 6.0.8, 7.0.1
  7. Mautic user without privileged access to the Marketplace can install and uninstall composer packages
    Critical CVE-2025-13828 >= 4.0.0, < 4.4.18, >= 5.0.0, < 5.2.9, >= 6.0.0, < 6.0.7 4.4.18, 5.2.9, 6.0.7
  8. Mautic vulnerable to reflected XSS in lead:addLeadTags - Quick Add this entry
    Medium CVE-2025-9823 >= 4.4.0, < 4.4.17, >= 5.0.0-alpha, < 5.2.8, >= 6.0.0-alpha, < 6.0.5 4.4.17, 5.2.8, 6.0.5
  9. Mautic allows Improper Authorization in Reporting API
    High · 7.7 CVE-2024-47053 >= 1.0.1, < 5.2.3 5.2.3
  10. Mautic allows Remote Code Execution and File Deletion in Asset Uploads
    Critical · 9.1 CVE-2024-47051 < 5.2.3 5.2.3
  11. Mautic vulnerable to Improper Access Control in UI upgrade process
    High · 7.0 CVE-2022-25768 >= 1.1.3, < 4.4.13, >= 5.0.0-alpha, < 5.1.1 4.4.13, 5.1.1
  12. Mautic is vulnerable to XSS vulnerability
    Critical · 9.6 CVE-2020-35125 < 2.16.5, >= 3.0.0, < 3.2.4 2.16.5, 3.2.4
  13. Mautic Sensitive Data Exposure due to inadequate user permission settings
    High · 8.3 CVE-2022-25776 >= 1.0.2, < 4.4.12, >= 5.0.0-alpha, < 5.0.4 4.4.12, 5.0.4
  14. Mautic vulnerable to Relative Path Traversal / Arbitrary File Deletion due to GrapesJS builder
    High · 8.1 CVE-2021-27916 >= 3.3.0, < 4.4.12, >= 5.0.0-alpha, < 5.0.4 4.4.12, 5.0.4
  15. Mautic vulnerable to stored cross-site scripting in description field
    High · 7.6 CVE-2021-27915 >= 1.0.0-beta2, < 4.4.12 4.4.12
  16. Cross-site Scripting vulnerability in Mautic's tracking pixel functionality
    Critical · 9.6 CVE-2022-25772 < 4.3.0 4.3.0
  17. Mautic stored Cross-site Scripting (XSS)
    Critical · 9.0 CVE-2020-35129 < 3.2.4 3.2.4
  18. Mautic stored Cross-site Scripting (XSS)
    Critical · 9.0 CVE-2020-35128 >= 3.2.0, < 3.2.4, >= 2.0.0, < 2.16.5 3.2.4, 2.16.5
  19. Sensitive Cookie Without HttpOnly and Secure Flag
    High · 7.5 CVE-2017-1000046 < 2.1.1 2.1.1
  20. Mautic Cross-Site Request Forgery (CSRF)
    High · 8.8 CVE-2017-8874 = 1.4.1 no fix
Show more (7) Showing 20 of 27

Know which vulnerabilities affect your application

With the DockRay integration and software inventory enabled, DockRay checks reported component versions against known vulnerabilities and notifies you about confirmed matches. Coverage depends on the supported technology and available advisory data.

Connect your application
DockRay newsletter

Application security in your inbox

Important vulnerabilities, actionable guidance and practical advice for your applications. Choose your technologies and follow what matters to your project.

  • A daily digest of new vulnerabilities, critical ones included.
  • Notifications about important updates.
  • Practical advice on application security and monitoring.

Leave empty to receive updates for every technology.

Privacy policy

Free to subscribe. Unsubscribe with one click in any email.