CVE-2007-6573: Qksoft Qk Smtp Server 3

High severity, CVSS 7.8. EPSS: 1.6% chance of exploitation in the next 30 days.

QK SMTP Server 3 allows remote attackers to cause a denial of service (daemon crash) via a long (1) HELO, (2) MAIL FROM, or (3) RCPT TO command; or (4) a long string in the message sent after the DATA command; possibly a related issue to CVE-2006-5551.

Affected products

• Qksoft Qk Smtp Server 3: any version

Published 2007-12-28. Last modified 2026-06-16.