CVE-2025-34409
MailEnable versions prior to 10.54 contain a reflected cross-site scripting (XSS) vulnerability in the Failed parameter of /Mondo/lang/sys/Forms/MAI/AddRecipientsResult.aspx. The Failed value is not properly sanitized when processed via a GET request and is reflected in the response, allowing an attacker to break out of existing markup and inject arbitrary script. A remote attacker can supply a crafted payload that closes an existing HTML list element, inserts attacker-controlled JavaScript, and comments out remaining code, leading to script execution in a victim’s browser when the victim visits a malicious link.
Successful exploitation can redirect victims to malicious sites, steal non-HttpOnly cookies, inject arbitrary HTML or CSS, and perform actions as the authenticated user.
- No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
ATT&CK techniques
2Techniques this CVE enables - linked via CWECAPECATT&CK. High◆ = named directly in ATT&CK or Nuclei templates.
▤ Build a SIEM detection for these techniquesCAPEC attack patterns
6Attack patterns this CVE enables - the bridge from weakness to ATT&CK technique.