Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) in EspoCRM - CVE-2026-33657
Published: April 14, 2026
Vulnerability identifier: #VU125918
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-33657
CWE-ID: CWE-80
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: EspoCRM
Affected software:
EspoCRM
EspoCRM
Detailed vulnerability description
The vulnerability allows a remote user to inject arbitrary HTML into system-generated email notifications.
The vulnerability exists due to improper neutralization of HTML content in email notification templates when rendering Markdown-derived stream note content. A remote user can submit a specially crafted stream note to inject arbitrary HTML into system-generated email notifications.
User interaction is required to open the email notification, and the @mention feature enables targeted delivery to specific users.
How to mitigate CVE-2026-33657
Install security update from vendor's website.