CVE-2026-9811

MEDIUM
Published May 29, 2026 Modified May 29, 2026 CWE-79

Description

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. 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.

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CVSS v3.1 Score

5.4
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

EPSS — Exploit Prediction

0.0013
Probability of exploitation
0.03%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

References

Frequently Asked Questions

What is CVE-2026-9811? +
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. 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. It has a CVSS v3.1 base score of 5.4 (MEDIUM).
How severe is CVE-2026-9811? +
CVE-2026-9811 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0013, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-9811? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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