CVE-2001-1581: Clearswift Limited Mailsweeper

High severity, CVSS 7.5. EPSS: 1.3% chance of exploitation in the next 30 days.

The File Blocker feature in Clearswift MAILsweeper for SMTP 4.2 allows remote attackers to bypass e-mail attachment filtering policies via a modified name in a Content-Type header.

Affected products

• Clearswift Limited Mailsweeper: version 4.2 only

Published 2001-12-31. Last modified 2026-06-16.