CVE-2021-3448

Public Exploit

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.

Category

4.0
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.04%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org
Affected: n/a dnsmasq
Published at:
Updated at:

References

Link Tags
https://bugzilla.redhat.com/show_bug.cgi?id=1939368 patch exploit third party advisory issue tracking
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GHURNEHHUBSW45KMIZ4FNBCSUPWPGV5V/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FHG7GWSQWKF7JXIMLOGJBKZWBB4VIAJ7/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CVTJUOFFFHINLKWAOC2ZSC5MOPD4SJ24/ vendor advisory
https://security.gentoo.org/glsa/202105-20 third party advisory vendor advisory
https://www.oracle.com/security-alerts/cpujan2022.html third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-3448?
CVE-2021-3448 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3448?
To fix CVE-2021-3448, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-3448 being actively exploited in the wild?
It is possible that CVE-2021-3448 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-3448?
CVE-2021-3448 affects n/a dnsmasq.
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