RHSA-2021:4153 - Security Advisory

Topic

An update for dnsmasq is now available for Red Hat Enterprise Linux 8.

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: fixed outgoing port used when --server is used with an interface name (CVE-2021-3448)

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.

Additional Changes:

For detailed information on changes in this release, see the Red Hat Enterprise Linux 8.5 Release Notes linked from the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 8 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.6 x86_64
• Red Hat Enterprise Linux Server - AUS 8.6 x86_64
• Red Hat Enterprise Linux for IBM z Systems 8 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 8.6 s390x
• Red Hat Enterprise Linux for Power, little endian 8 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.6 ppc64le
• Red Hat Enterprise Linux Server - TUS 8.6 x86_64
• Red Hat Enterprise Linux for ARM 64 8 aarch64
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.6 aarch64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.6 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.6 x86_64

Fixes

• BZ - 1921153 - failed to send packet: Network is unreachable when resolution is busy.
• BZ - 1927973 - dnsmasq --bind-dynamic stops replying to upstream queries
• BZ - 1939368 - CVE-2021-3448 dnsmasq: fixed outgoing port used when --server is used with an interface name
• BZ - 1947039 - typo in dnsmasq man page

CVEs

• CVE-2021-3448

References

• https://access.redhat.com/security/updates/classification/#moderate
• https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/8.5_release_notes/