CVE-2021-3448Improperly Implemented Security Check for Standard in Dnsmasq

Severity
4.0MEDIUMNVD
EPSS
0.0%
top 87.49%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedApr 8
Latest updateSep 7

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.

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:NExploitability: 2.2 | Impact: 1.4

Affected Packages4 packages

Also affects: Fedora 32, 33, 34, Enterprise Linux 8.0

Patches

🔴Vulnerability Details

3
GHSA
GHSA-vvf4-c8p4-89v5: A flaw was found in dnsmasq in versions before 22022-05-24
CVEList
CVE-2021-3448: A flaw was found in dnsmasq in versions before 22021-04-08
OSV
CVE-2021-3448: A flaw was found in dnsmasq in versions before 22021-04-08

📋Vendor Advisories

6
Ubuntu
Dnsmasq vulnerability2022-09-07
Oracle
Oracle Oracle Communications Risk Matrix: Configuration (dnsmasq) — CVE-2021-34482022-01-15
Ubuntu
Dnsmasq vulnerability2021-06-02
Microsoft
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 netwo2021-04-13
Red Hat
dnsmasq: fixed outgoing port used when --server is used with an interface name2021-03-12
CVE-2021-3448 — Thekelleys Dnsmasq vulnerability | cvebase