Sign in
Deutsch English Español Polski
High

Stored XSS vulnerability on Bounce Management Callback

  • Disclosed: 01.09.2021
  • Updated: 11.10.2026 10:22

Impact

Insufficient sanitization / filtering allows for arbitrary JavaScript Injection in Mautic using the bounce management callback function. The values submitted in the "error" and "error_related_to" parameters of the POST request of the bounce management callback will be permanently stored and executed once the details page of an affected lead is opened by a Mautic user.

An attacker with access to the bounce management callback function (identified with the Mailjet webhook, but it is assumed this will work uniformly across all kinds of webhooks) can inject arbitrary JavaScript Code into the "error" and "error_related_to" parameters of the POST request (POST /mailer/<product / webhook>/callback). It is noted that there is no authentication needed to access this function.

The JavaScript Code is stored permanently in the web application and executed every time an authenticated user views the details page of a single contact / lead in Mautic. This means, arbitrary code can be executed to, e.g., steal or tamper with information.

Patches

Upgrade to 3.3.4 or 4.0.0

Workarounds

No

References

https://github.com/mautic/mautic/releases/tag/3.3.4 https://github.com/mautic/mautic/releases/tag/4.0.0

For more information

If you have any questions or comments about this advisory:

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Composer package mautic/core < 3.3.4, >= 4.0.0-alpha1, < 4.0.0 3.3.4, 4.0.0

References

CVSS score 8.2/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:N
Weakness (CWE)
CWE-79
Platform
Composer
Package
mautic/core
Disclosed
01.09.2021
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-86pv-95mj-7w5f - 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 allows Improper Authorization in Reporting API
    High · 7.7 CVE-2024-47053 >= 1.0.1, < 5.2.3 5.2.3
  9. Mautic allows Remote Code Execution and File Deletion in Asset Uploads
    Critical · 9.1 CVE-2024-47051 < 5.2.3 5.2.3
  10. 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
  11. 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
  12. 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
  13. 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
  14. 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
  15. Cross-site Scripting vulnerability in Mautic's tracking pixel functionality
    Critical · 9.6 CVE-2022-25772 < 4.3.0 4.3.0
  16. Mautic stored Cross-site Scripting (XSS)
    Critical · 9.0 CVE-2020-35129 < 3.2.4 3.2.4
  17. 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
  18. Sensitive Cookie Without HttpOnly and Secure Flag
    High · 7.5 CVE-2017-1000046 < 2.1.1 2.1.1
  19. Mautic Cross-Site Request Forgery (CSRF)
    High · 8.8 CVE-2017-8874 = 1.4.1 no fix
  20. Stored XSS vulnerability on Bounce Management Callback this entry
    High · 8.2 CVE-2021-27910 < 3.3.4, >= 4.0.0-alpha1, < 4.0.0 3.3.4, 4.0.0
Show more (6) Showing 20 of 26

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.