RHSA-2021:0156 — Security Advisory
Red Hat Security Advisory: dnsmasq security update
Severity
ModerateRed Hat Product Security
Products
Official CSAF product identity
Published · January 19, 2021
Updated · June 28, 2026
Topic
An update for dnsmasq is now available for Red Hat Enterprise Linux 7.4 Advanced Update Support, Red Hat Enterprise Linux 7.4 Telco Extended Update Support, and Red Hat Enterprise Linux 7.4 Update Services for SAP Solutions.
Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
Description
The dnsmasq packages contain Dnsmasq, a lightweight DNS (Domain Name Server) forwarder and DHCP (Dynamic Host Configuration Protocol) server.
Security Fix(es):
-
dnsmasq: loose address/port check in reply_query() makes forging replies easier for an off-path attacker (CVE-2020-25684)
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dnsmasq: loose query name check in reply_query() makes forging replies easier for an off-path attacker (CVE-2020-25685)
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dnsmasq: multiple queries forwarded for the same name makes forging replies easier for an off-path attacker (CVE-2020-25686)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.