CVE-2021-3448
MEDIUMdnsmasq < 2.85 - DNS Cache Poisoning via Fixed Port Query Forwarding
Title source: llmDescription
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.
References (6)
Core 6
Core References
Exploit, Issue Tracking, Patch, Third Party Advisory x_refsource_misc
https://bugzilla.redhat.com/show_bug.cgi?id=1939368
Mailing List, Third Party Advisory vendor-advisory
x_refsource_fedora
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GHURNEHHUBSW45KMIZ4FNBCSUPWPGV5V/
Mailing List, Third Party Advisory vendor-advisory
x_refsource_fedora
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FHG7GWSQWKF7JXIMLOGJBKZWBB4VIAJ7/
Mailing List, Third Party Advisory vendor-advisory
x_refsource_fedora
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CVTJUOFFFHINLKWAOC2ZSC5MOPD4SJ24/
Third Party Advisory vendor-advisory
x_refsource_gentoo
https://security.gentoo.org/glsa/202105-20
Patch, Third Party Advisory x_refsource_misc
https://www.oracle.com/security-alerts/cpujan2022.html
Scores
CVSS v3
4.0
EPSS
0.0199
EPSS Percentile
78.0%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-358
Status
published
Products (6)
fedoraproject/fedora
32
fedoraproject/fedora
33
fedoraproject/fedora
34
oracle/communications_cloud_native_core_network_function_cloud_native_environment
1.9.0
redhat/enterprise_linux
8.0
thekelleys/dnsmasq
< 2.85
Published
Apr 08, 2021
Tracked Since
Feb 18, 2026