Vulnerability Note VU#149953
ISC "dhcrelay" fails to limit hop count when malicious bootp packet is received
A vulnerability in the Internet Software Consortium's "dhcrelay" makes it possible for a remote attacker to use dhcrelay to launch a denial-of-service attack against a victim dhcp server.
The Internet Software Consortium (ISC) produces a "freely redistributable reference implementation of all aspects of the DHCP protocol, through a suite of tools." One of these tools is a dhcp relay agent (dhcrelay). From the dhcrelay man page:
The Internet Software Consortium DHCP Relay Agent, dhcrelay, provides a means for relaying DHCP and BOOTP requests from a subnet to which no DHCP server is directly connected to one or more DHCP servers on other subnets. The DHCP Relay Agent listens for DHCP and BOOTP queries and responses. When a query is received from a client, dhcrelay forwards it to the list of DHCP servers specified on the command line. When a reply is received from a server, it is broadcast or unicast (according to the relay agent's ability or the client's request) on the network from which the original request came.
A remote attacker can use dhcrelay to launch a denial-of-service attack against DHCP servers configured to communicate with the dhcrelay host.
Apply a patch from your vendor.
Systems Affected (Learn More)
|Vendor||Status||Date Notified||Date Updated|
|Conectiva Linux||Affected||-||07 Apr 2003|
|Debian||Affected||-||04 Feb 2003|
|Internet Software Consortium||Affected||04 Feb 2003||05 Feb 2003|
|OpenPKG||Affected||-||26 Feb 2003|
|Red Hat Inc.||Affected||-||01 Apr 2003|
|Apple Computer Inc.||Not Affected||-||05 Feb 2003|
|Cisco Systems Inc.||Not Affected||-||13 Feb 2003|
|Hewlett-Packard Company||Not Affected||04 Feb 2003||05 Feb 2003|
|Ingrian Networks||Not Affected||04 Feb 2003||05 Feb 2003|
|Lotus Software||Not Affected||-||05 Feb 2003|
|Network Appliance||Not Affected||-||04 Feb 2003|
|Xerox Corporation||Not Affected||-||30 May 2003|
CVSS Metrics (Learn More)
This vulnerability was discovered by Florian Lohoff and reported to the BugTraq mailing list on January 15, 2003.
This document was written by Ian A Finlay.
- CVE IDs: CAN-2003-0039
- Date Public: 15 Jan 2003
- Date First Published: 04 Feb 2003
- Date Last Updated: 30 May 2003
- Severity Metric: 8.10
- Document Revision: 17
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