CVE-2026-38444
osTicket v1.18.3 is vulnerable to Stored Cross-Site Scripting (XSS) via the email From-header display name. The value is extracted without sanitization in include/class.mailparse.php and stored raw in the poster field of ost_thread_entry. When an unauthenticated attacker sends a reply email to an existing ticket from an unregistered address with an XSS payload in the From display name.
Weakness
osTicket v1.18.3 is vulnerable to Stored Cross-Site Scripting (XSS) via the email From-header display name. The value is extracted without sanitization in include/class.mailparse.php and stored raw in the poster field of ost_thread_entry. When an unauthenticated attacker sends a reply email to an existing ticket from an unregistered address with an XSS payload in the From display name.
References
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