Stored Cross-Site Scripting Vulnerability in GFI MailEssentials AI
CVE-2026-23604

5.1MEDIUM

Key Information:

Vendor

Gfi Software

Status
Mailessentials Ai
Vendor
CVE Published:
19 February 2026

What is CVE-2026-23604?

GFI MailEssentials AI versions prior to 22.4 are susceptible to a stored cross-site scripting (XSS) vulnerability due to improper handling of user-provided data within the Keyword Filtering rule creation workflow. An authenticated user can inject HTML or JavaScript code into the ctl00$ContentPlaceHolder1$pv1$TXB_RuleName parameter to /MailEssentials/pages/MailSecurity/contentchecking.aspx. The malicious script is then stored and executed in the context of any user viewing the management interface, potentially exposing sensitive information and allowing unauthorized actions.

Affected Version(s)

MailEssentials AI 0 < 22.4

References

https://gfi.ai/products-and-solutions/network-security-so...
release-notespatch
https://www.vulncheck.com/advisories/gfi-mailessentials-a...
third-party-advisory

CVSS V4

Score:
5.1
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Alex Williams from Pellera Technologies
VulnCheck
.