RHSA-2021:0151 — Security Advisory
Red Hat Security Advisory: dnsmasq security update
Severity
ImportantRed 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 8.2 Extended Update Support.
Red Hat Product Security has rated this update as having a security impact of Important. 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):
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dnsmasq: heap-based buffer overflow in sort_rrset() when DNSSEC is enabled (CVE-2020-25681)
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dnsmasq: buffer overflow in extract_name() due to missing length check when DNSSEC is enabled (CVE-2020-25682)
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dnsmasq: heap-based buffer overflow with large memcpy in get_rdata() when DNSSEC is enabled (CVE-2020-25683)
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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)
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dnsmasq: heap-based buffer overflow with large memcpy in sort_rrset() when DNSSEC is enabled (CVE-2020-25687)
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.