CVE-2026-9811 — core
MEDIUMCVE-2026-9811 is a medium-severity (CVSS 5.4) Cross-site Scripting (XSS) vulnerability in mautic/core. A fix is available for mautic/core — see the affected versions and patch details below.
Mautic has Stored Cross-Site Scripting (XSS) in Project Option Selector
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-9811.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-9811 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 394,803 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
mautic/coreReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Summary
A stored Cross-Site Scripting (XSS) vulnerability exists in the project selector component of Mautic 7. When rendering selection menus for associating projects with system entities, the application fails to sanitize project names returned via AJAX before injecting them into the DOM as option fields. An authenticated user with permissions to create projects can exploit this to store a malicious script payload in the project's name.
Impact
When another administrative user subsequently opens an entity editor containing the project selector, the injected script executes within the context of their active browser session. This could allow an attacker to hijack the session, perform unauthorized state coordination, or access organizational data within the dashboard.
Patched Versions
This security issue has been addressed in the following release:
- 7.1.2
Note: Mautic 6.x, 5.x, and 4.x branches do not contain the Projects feature or the associated AJAX selector and are not affected by this vulnerability. For general security support regarding legacy Mautic 4 releases, please refer to the ELTS page.
Workarounds
There are no official workarounds. To mitigate this vulnerability without upgrading, restrict project creation and modification permissions to trusted administrative users.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | mautic/core | ≥ 7.0.0&&< 7.1.2 | 7.1.2composer require mautic/core:^7.1.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for mautic/core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update mautic/core to 7.1.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-9811 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
Frequently Asked Questions
Is CVE-2026-9811 in your dependencies?
Find it across Packagist, including transitive dependencies.