1) Insufficient verification of data authenticity

EUVDB-ID: #VU52065

Risk: Medium

CVSSv3.1:

CVE-ID: CVE-2021-3448

CWE-ID: CWE-345 - Insufficient Verification of Data Authenticity

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a DNS Cache Poisoning attack.

The vulnerability exists due to dnsmasq relies only on transmission ID when processing DNS queries and uses the same port for outgoing requests, when configured to given network interface. A remote attacker can guess the random transmission ID to forge a reply and get it accepted by dnsmasq.As a result, an attacker can perform a DNS Cache Poisoning attack.

Mitigation

Update the affected package dnsmasq to the latest version.

Vulnerable software versions

Ubuntu: 20.10, 21.04, 20.04, 18.04

dnsmasq-base (Ubuntu package): before 2.80-1.1ubuntu1.4

dnsmasq-utils (Ubuntu package): before 2.80-1.1ubuntu1.4

dnsmasq (Ubuntu package): before 2.80-1.1ubuntu1.4

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CPE2.3

• cpe:2.3:o:canonical:ubuntu:20.10:*:*:*:*:*:*:*

External links

http://ubuntu.com/security/notices/USN-4976-1

Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?