CVE-2001-1056: Linux Kernel

High severity, CVSS 7.5. EPSS: 2.4% chance of exploitation in the next 30 days.

IRC DCC helper in the ip_masq_irc IP masquerading module 2.2 allows remote attackers to bypass intended firewall restrictions by causing the target system to send a "DCC SEND" request to a malicious server which listens on port 6667, which may cause the module to believe that the traffic is a valid request and allow the connection to the port specified in the DCC SEND request.

Affected products

• Linux Linux Kernel: after 2.0.1, up to and including 2.0.18; from 2.2.0, up to and including 2.2.18

Published 2001-07-30. Last modified 2026-06-16.