DNS Server Spoofed Request Amplification DDoS

high Nessus Plugin ID 35450
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Synopsis

The remote DNS server could be used in a distributed denial of service attack.

Description

The remote DNS server answers to any request. It is possible to query the name servers (NS) of the root zone ('.') and get an answer that is bigger than the original request. By spoofing the source IP address, a remote attacker can leverage this 'amplification' to launch a denial of service attack against a third-party host using the remote DNS server.

Solution

Restrict access to your DNS server from public network or reconfigure it to reject such queries.

See Also

https://isc.sans.edu/diary/DNS+queries+for+/5713

Plugin Details

Severity: High

ID: 35450

File Name: dns_amplification.nasl

Version: 1.16

Type: remote

Family: DNS

Published: 1/22/2009

Updated: 8/21/2020

Dependencies: dns_server.nasl

Risk Information

CVSS Score Source: CVE-2006-0987

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: High

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Vulnerability Information

Required KB Items: DNS/udp/53

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 2/28/2006

Reference Information

CVE: CVE-2006-0987