| VID |
13004 |
| Severity |
20 |
| Port |
|
| Protocol |
ICMP |
| Class |
Protocol |
| Detailed Description |
The host answers to an ICMP netmask request and sent us its netmask. An attacker can use this information to understand how a target network is set up and how the routing is done. And by determining the netmasks of various machines in the target network, the attacker can better map the target subnet structure and infer trust relationships.
* References:
http://www.iss.net/security_center/static/306.php |
| Recommendation |
Configure your firewall or filtering router to block the incoming ICMP netmask requests (17), and the outgoing ICMP netmask replies (18). |
| Related URL |
CVE-1999-0524 (CVE) |
| Related URL |
(SecurityFocus) |
| Related URL |
(ISS) |
|
