VULNERABILITY INTELLIGENCE

CVE-2021-3448

CVSS score4 MEDIUM
EPSS probability2.28%
CISA KEVNot currently listed
Published2021-04-08
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N

Description

A flaw was found in dnsmasq in versions before 2.85. When configured to use a specific server for a given network interface, dnsmasq uses a fixed port while forwarding queries. An attacker on the network, able to find the outgoing port used by dnsmasq, only needs to guess the random transmission ID to forge a reply and get it accepted by dnsmasq. This flaw makes a DNS Cache Poisoning attack much easier. The highest threat from this vulnerability is to data integrity.

Weakness classification

  • secalert@redhat.com: CWE-358
  • nvd@nist.gov: NVD-CWE-Other

Primary references