CVE-2026-9809
Published: 29 May 2026
Summary
CVE-2026-9809 is a high-severity Cross-site Scripting (CWE-79) vulnerability. Its CVSS base score is 7.6 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique JavaScript (T1059.007); ranked at the 5.9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-33279
Vulnerability details
A stored Cross-Site Scripting (XSS) vulnerability exists in the Projects component of Mautic 7. When displaying project tags and popovers on administrative detail views (such as campaigns, emails, or forms), user-supplied project names are rendered without proper sanitization. An authenticated…
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user with permissions to create or edit projects can exploit this to inject malicious script payloads. When an administrative user views an entity associated with a compromised project and hovers over its tag, the injected script executes within the context of their active browser session. This could allow an attacker to perform administrative actions on behalf of the victim, alter system configurations, or exfiltrate sensitive data.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Stored XSS enables JavaScript execution (T1059.007) in admin browser session, facilitating session hijacking/actions (T1185).
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.
Validates web inputs to reject script-related content that could produce XSS.
Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.