Summary
XSS vulnerability leveraged through referrers could allow un-authorized admin access in Mautic
Workarounds
None
For more information
If you have any questions or comments about this advisory:
- Post in https://forum.mautic.org/c/support
- Email us at [email protected]
Impact
This is a cross-site scripting vulnerability which affects every version of Mautic and could allow an attacker unauthorised administrator level access to Mautic.
This vulnerability was reported by Naveen Sunkavally at Horizon3.ai.
Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
Upgrade to 3.2.4 or 2.16.5.
Link to patch for 2.x versions: https://github.com/mautic/mautic/compare/2.16.4...2.16.5.diff
Link to patch for 3.x versions: https://github.com/mautic/mautic/compare/3.2.2...3.2.4.diff
Frequently Asked Questions
- What is CVE-2020-35124? CVE-2020-35124 is a critical-severity cross-site scripting (XSS) vulnerability in mautic/core (composer), affecting versions >= 3.0.0, < 3.2.4. It is fixed in 3.2.4, 2.16.5. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
- Which versions of mautic/core are affected by CVE-2020-35124? mautic/core (composer) versions >= 3.0.0, < 3.2.4 is affected.
- Is there a fix for CVE-2020-35124? Yes. CVE-2020-35124 is fixed in 3.2.4, 2.16.5. Upgrade to this version or later.
- Is CVE-2020-35124 exploitable, and should I be worried? Whether CVE-2020-35124 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2020-35124 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2020-35124?
- Upgrade
mautic/coreto 3.2.4 or later - Upgrade
mautic/coreto 2.16.5 or later
- Upgrade