Skip to navigation Skip to main content

Utilities

  • Subscriptions
  • Downloads
  • Red Hat Console
  • Get Support
Red Hat Customer Portal
  • Subscriptions
  • Downloads
  • Red Hat Console
  • Get Support
  • Products

    Top Products

    • Red Hat Enterprise Linux
    • Red Hat OpenShift
    • Red Hat Ansible Automation Platform
    All Products

    Downloads and Containers

    • Downloads
    • Packages
    • Containers

    Top Resources

    • Documentation
    • Product Life Cycles
    • Product Compliance
    • Errata
  • Knowledge

    Red Hat Knowledge Center

    • Knowledgebase Solutions
    • Knowledgebase Articles
    • Customer Portal Labs
    • Errata

    Top Product Docs

    • Red Hat Enterprise Linux
    • Red Hat OpenShift
    • Red Hat Ansible Automation Platform
    All Product Docs

    Training and Certification

    • About
    • Course Index
    • Certification Index
    • Skill Assessment
  • Security

    Red Hat Product Security Center

    • Security Updates
    • Security Advisories
    • Red Hat CVE Database
    • Errata

    References

    • Security Bulletins
    • Security Measurement
    • Severity Ratings
    • Security Data

    Top Resources

    • Security Labs
    • Backporting Policies
    • Security Blog
  • Support

    Red Hat Support

    • Support Cases
    • Troubleshoot
    • Get Support
    • Contact Red Hat Support

    Red Hat Community Support

    • Customer Portal Community
    • Community Discussions
    • Red Hat Accelerator Program

    Top Resources

    • Product Life Cycles
    • Customer Portal Labs
    • Red Hat JBoss Supported Configurations
    • Red Hat Insights
Or troubleshoot an issue.

Select Your Language

  • English
  • Français
  • 한국어
  • 日本語
  • 中文 (中国)

Infrastructure and Management

  • Red Hat Enterprise Linux
  • Red Hat Satellite
  • Red Hat Subscription Management
  • Red Hat Insights
  • Red Hat Ansible Automation Platform

Cloud Computing

  • Red Hat OpenShift
  • Red Hat OpenStack Platform
  • Red Hat OpenShift
  • Red Hat OpenShift AI
  • Red Hat OpenShift Dedicated
  • Red Hat Advanced Cluster Security for Kubernetes
  • Red Hat Advanced Cluster Management for Kubernetes
  • Red Hat Quay
  • Red Hat OpenShift Dev Spaces
  • Red Hat OpenShift Service on AWS

Storage

  • Red Hat Gluster Storage
  • Red Hat Hyperconverged Infrastructure
  • Red Hat Ceph Storage
  • Red Hat OpenShift Data Foundation

Runtimes

  • Red Hat Runtimes
  • Red Hat JBoss Enterprise Application Platform
  • Red Hat Data Grid
  • Red Hat JBoss Web Server
  • Red Hat build of Keycloak
  • Red Hat support for Spring Boot
  • Red Hat build of Node.js
  • Red Hat build of Quarkus

Integration and Automation

  • Red Hat Application Foundations
  • Red Hat Fuse
  • Red Hat AMQ
  • Red Hat 3scale API Management
All Products
Red Hat Product Errata RHSA-2021:0155 - Security Advisory
Issued:
2021-01-19
Updated:
2021-01-19

RHSA-2021:0155 - Security Advisory

  • Overview
  • Updated Packages

Synopsis

Moderate: dnsmasq security update

Type/Severity

Security Advisory: Moderate

Red Hat Insights patch analysis

Identify and remediate systems affected by this advisory.

View affected systems

Topic

An update for dnsmasq is now available for Red Hat Enterprise Linux 7.6 Extended Update Support.

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)
  • dnsmasq: loose query name check in reply_query() makes forging replies easier for an off-path attacker (CVE-2020-25685)
  • 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.

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 - Extended Update Support 7.6 x86_64
  • Red Hat Enterprise Linux Server - AUS 7.6 x86_64
  • Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.6 s390x
  • Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.6 ppc64
  • Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.6 ppc64le
  • Red Hat Enterprise Linux Server - TUS 7.6 x86_64
  • Red Hat Enterprise Linux for Power 9 7 ppc64le
  • Red Hat Enterprise Linux EUS Compute Node 7.6 x86_64
  • Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.6 ppc64le
  • Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.6 x86_64
  • Red Hat Enterprise Linux for IBM System z (Structure A) 7 s390x

Fixes

  • BZ - 1889686 - CVE-2020-25684 dnsmasq: loose address/port check in reply_query() makes forging replies easier for an off-path attacker
  • BZ - 1889688 - CVE-2020-25685 dnsmasq: loose query name check in reply_query() makes forging replies easier for an off-path attacker
  • BZ - 1890125 - CVE-2020-25686 dnsmasq: multiple queries forwarded for the same name makes forging replies easier for an off-path attacker

CVEs

  • CVE-2020-25684
  • CVE-2020-25685
  • CVE-2020-25686

References

  • https://access.redhat.com/security/updates/classification/#moderate
  • https://access.redhat.com/security/vulnerabilities/RHSB-2021-001
Note: More recent versions of these packages may be available. Click a package name for more details.

Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.6

SRPM
dnsmasq-2.76-7.el7_6.2.src.rpm SHA-256: d4d05db2547a6dd64fec4bbb9e7e9580363e207ca8aa7f5971247db8e7d95964
x86_64
dnsmasq-2.76-7.el7_6.2.x86_64.rpm SHA-256: e2de2356823a0a9ff4ac840d351b608f4b3372cb5c0b2354f67842d8b44b4721
dnsmasq-debuginfo-2.76-7.el7_6.2.x86_64.rpm SHA-256: 78431f1fe82ab3d021f5694b74eb751eeef75e028f36b1f0201f1a1c75ad066d
dnsmasq-debuginfo-2.76-7.el7_6.2.x86_64.rpm SHA-256: 78431f1fe82ab3d021f5694b74eb751eeef75e028f36b1f0201f1a1c75ad066d
dnsmasq-utils-2.76-7.el7_6.2.x86_64.rpm SHA-256: b6506e04e5971428a468ee3dd9f2fdbb54fd1f15d7ef1a958e0384a0307f4d3b

Red Hat Enterprise Linux Server - AUS 7.6

SRPM
dnsmasq-2.76-7.el7_6.2.src.rpm SHA-256: d4d05db2547a6dd64fec4bbb9e7e9580363e207ca8aa7f5971247db8e7d95964
x86_64
dnsmasq-2.76-7.el7_6.2.x86_64.rpm SHA-256: e2de2356823a0a9ff4ac840d351b608f4b3372cb5c0b2354f67842d8b44b4721
dnsmasq-debuginfo-2.76-7.el7_6.2.x86_64.rpm SHA-256: 78431f1fe82ab3d021f5694b74eb751eeef75e028f36b1f0201f1a1c75ad066d
dnsmasq-debuginfo-2.76-7.el7_6.2.x86_64.rpm SHA-256: 78431f1fe82ab3d021f5694b74eb751eeef75e028f36b1f0201f1a1c75ad066d
dnsmasq-utils-2.76-7.el7_6.2.x86_64.rpm SHA-256: b6506e04e5971428a468ee3dd9f2fdbb54fd1f15d7ef1a958e0384a0307f4d3b

Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.6

SRPM
dnsmasq-2.76-7.el7_6.2.src.rpm SHA-256: d4d05db2547a6dd64fec4bbb9e7e9580363e207ca8aa7f5971247db8e7d95964
s390x
dnsmasq-2.76-7.el7_6.2.s390x.rpm SHA-256: f4853087e75e26b72920f51fddd95d7a2c9921778c3e6901b27c669c19f0ffa6
dnsmasq-debuginfo-2.76-7.el7_6.2.s390x.rpm SHA-256: 77127481a2f73f32dc88c42bbd30a6906a631a3bedf9b6d4c724b98c4aa4eff2
dnsmasq-debuginfo-2.76-7.el7_6.2.s390x.rpm SHA-256: 77127481a2f73f32dc88c42bbd30a6906a631a3bedf9b6d4c724b98c4aa4eff2
dnsmasq-utils-2.76-7.el7_6.2.s390x.rpm SHA-256: 7e57551f2f69cd288cb90df2d5db1566ef47ba238c10f8a829d957c09d105d81

Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.6

SRPM
dnsmasq-2.76-7.el7_6.2.src.rpm SHA-256: d4d05db2547a6dd64fec4bbb9e7e9580363e207ca8aa7f5971247db8e7d95964
ppc64
dnsmasq-2.76-7.el7_6.2.ppc64.rpm SHA-256: 8974200e6b1895dd06c668fb7530483ae1284d27ffff3a0bdeabf71228cde2a8
dnsmasq-debuginfo-2.76-7.el7_6.2.ppc64.rpm SHA-256: 26dc07cfd78913adca78b2cefe4a2ba6980a22ad72e9aa22780a4bdfb854f798
dnsmasq-debuginfo-2.76-7.el7_6.2.ppc64.rpm SHA-256: 26dc07cfd78913adca78b2cefe4a2ba6980a22ad72e9aa22780a4bdfb854f798
dnsmasq-utils-2.76-7.el7_6.2.ppc64.rpm SHA-256: ca082c85bb2d7bfcf281abc21ad66e5dba44476737e33f04ab76b68c07b43414

Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.6

SRPM
dnsmasq-2.76-7.el7_6.2.src.rpm SHA-256: d4d05db2547a6dd64fec4bbb9e7e9580363e207ca8aa7f5971247db8e7d95964
ppc64le
dnsmasq-2.76-7.el7_6.2.ppc64le.rpm SHA-256: 07c3aa55fc2d6dbb1280d2804eb900eb4ad5fc8c4962a1248b7eb7c5be4db3b5
dnsmasq-debuginfo-2.76-7.el7_6.2.ppc64le.rpm SHA-256: f83b5d5c776daa29c21b5271cda5498e1126c7d42dc1951d89fa4906e0c81965
dnsmasq-debuginfo-2.76-7.el7_6.2.ppc64le.rpm SHA-256: f83b5d5c776daa29c21b5271cda5498e1126c7d42dc1951d89fa4906e0c81965
dnsmasq-utils-2.76-7.el7_6.2.ppc64le.rpm SHA-256: 0b738e4f49fef33e95fb361457d845dc1a270a766794cf6d201e3d01f6932978

Red Hat Enterprise Linux Server - TUS 7.6

SRPM
dnsmasq-2.76-7.el7_6.2.src.rpm SHA-256: d4d05db2547a6dd64fec4bbb9e7e9580363e207ca8aa7f5971247db8e7d95964
x86_64
dnsmasq-2.76-7.el7_6.2.x86_64.rpm SHA-256: e2de2356823a0a9ff4ac840d351b608f4b3372cb5c0b2354f67842d8b44b4721
dnsmasq-debuginfo-2.76-7.el7_6.2.x86_64.rpm SHA-256: 78431f1fe82ab3d021f5694b74eb751eeef75e028f36b1f0201f1a1c75ad066d
dnsmasq-debuginfo-2.76-7.el7_6.2.x86_64.rpm SHA-256: 78431f1fe82ab3d021f5694b74eb751eeef75e028f36b1f0201f1a1c75ad066d
dnsmasq-utils-2.76-7.el7_6.2.x86_64.rpm SHA-256: b6506e04e5971428a468ee3dd9f2fdbb54fd1f15d7ef1a958e0384a0307f4d3b

Red Hat Enterprise Linux for Power 9 7

SRPM
dnsmasq-2.76-7.el7_6.2.src.rpm SHA-256: d4d05db2547a6dd64fec4bbb9e7e9580363e207ca8aa7f5971247db8e7d95964
ppc64le
dnsmasq-2.76-7.el7_6.2.ppc64le.rpm SHA-256: 07c3aa55fc2d6dbb1280d2804eb900eb4ad5fc8c4962a1248b7eb7c5be4db3b5
dnsmasq-debuginfo-2.76-7.el7_6.2.ppc64le.rpm SHA-256: f83b5d5c776daa29c21b5271cda5498e1126c7d42dc1951d89fa4906e0c81965
dnsmasq-debuginfo-2.76-7.el7_6.2.ppc64le.rpm SHA-256: f83b5d5c776daa29c21b5271cda5498e1126c7d42dc1951d89fa4906e0c81965
dnsmasq-utils-2.76-7.el7_6.2.ppc64le.rpm SHA-256: 0b738e4f49fef33e95fb361457d845dc1a270a766794cf6d201e3d01f6932978

Red Hat Enterprise Linux EUS Compute Node 7.6

SRPM
dnsmasq-2.76-7.el7_6.2.src.rpm SHA-256: d4d05db2547a6dd64fec4bbb9e7e9580363e207ca8aa7f5971247db8e7d95964
x86_64
dnsmasq-2.76-7.el7_6.2.x86_64.rpm SHA-256: e2de2356823a0a9ff4ac840d351b608f4b3372cb5c0b2354f67842d8b44b4721
dnsmasq-debuginfo-2.76-7.el7_6.2.x86_64.rpm SHA-256: 78431f1fe82ab3d021f5694b74eb751eeef75e028f36b1f0201f1a1c75ad066d
dnsmasq-debuginfo-2.76-7.el7_6.2.x86_64.rpm SHA-256: 78431f1fe82ab3d021f5694b74eb751eeef75e028f36b1f0201f1a1c75ad066d
dnsmasq-utils-2.76-7.el7_6.2.x86_64.rpm SHA-256: b6506e04e5971428a468ee3dd9f2fdbb54fd1f15d7ef1a958e0384a0307f4d3b

Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.6

SRPM
dnsmasq-2.76-7.el7_6.2.src.rpm SHA-256: d4d05db2547a6dd64fec4bbb9e7e9580363e207ca8aa7f5971247db8e7d95964
ppc64le
dnsmasq-2.76-7.el7_6.2.ppc64le.rpm SHA-256: 07c3aa55fc2d6dbb1280d2804eb900eb4ad5fc8c4962a1248b7eb7c5be4db3b5
dnsmasq-debuginfo-2.76-7.el7_6.2.ppc64le.rpm SHA-256: f83b5d5c776daa29c21b5271cda5498e1126c7d42dc1951d89fa4906e0c81965
dnsmasq-debuginfo-2.76-7.el7_6.2.ppc64le.rpm SHA-256: f83b5d5c776daa29c21b5271cda5498e1126c7d42dc1951d89fa4906e0c81965
dnsmasq-utils-2.76-7.el7_6.2.ppc64le.rpm SHA-256: 0b738e4f49fef33e95fb361457d845dc1a270a766794cf6d201e3d01f6932978

Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.6

SRPM
dnsmasq-2.76-7.el7_6.2.src.rpm SHA-256: d4d05db2547a6dd64fec4bbb9e7e9580363e207ca8aa7f5971247db8e7d95964
x86_64
dnsmasq-2.76-7.el7_6.2.x86_64.rpm SHA-256: e2de2356823a0a9ff4ac840d351b608f4b3372cb5c0b2354f67842d8b44b4721
dnsmasq-debuginfo-2.76-7.el7_6.2.x86_64.rpm SHA-256: 78431f1fe82ab3d021f5694b74eb751eeef75e028f36b1f0201f1a1c75ad066d
dnsmasq-debuginfo-2.76-7.el7_6.2.x86_64.rpm SHA-256: 78431f1fe82ab3d021f5694b74eb751eeef75e028f36b1f0201f1a1c75ad066d
dnsmasq-utils-2.76-7.el7_6.2.x86_64.rpm SHA-256: b6506e04e5971428a468ee3dd9f2fdbb54fd1f15d7ef1a958e0384a0307f4d3b

Red Hat Enterprise Linux for IBM System z (Structure A) 7

SRPM
dnsmasq-2.76-7.el7_6.2.src.rpm SHA-256: d4d05db2547a6dd64fec4bbb9e7e9580363e207ca8aa7f5971247db8e7d95964
s390x
dnsmasq-2.76-7.el7_6.2.s390x.rpm SHA-256: f4853087e75e26b72920f51fddd95d7a2c9921778c3e6901b27c669c19f0ffa6
dnsmasq-debuginfo-2.76-7.el7_6.2.s390x.rpm SHA-256: 77127481a2f73f32dc88c42bbd30a6906a631a3bedf9b6d4c724b98c4aa4eff2
dnsmasq-debuginfo-2.76-7.el7_6.2.s390x.rpm SHA-256: 77127481a2f73f32dc88c42bbd30a6906a631a3bedf9b6d4c724b98c4aa4eff2
dnsmasq-utils-2.76-7.el7_6.2.s390x.rpm SHA-256: 7e57551f2f69cd288cb90df2d5db1566ef47ba238c10f8a829d957c09d105d81

The Red Hat security contact is secalert@redhat.com. More contact details at https://access.redhat.com/security/team/contact/.

Red Hat LinkedIn YouTube Facebook X, formerly Twitter

Quick Links

  • Downloads
  • Subscriptions
  • Support Cases
  • Customer Service
  • Product Documentation

Help

  • Contact Us
  • Customer Portal FAQ
  • Log-in Assistance

Site Info

  • Trust Red Hat
  • Browser Support Policy
  • Accessibility
  • Awards and Recognition
  • Colophon

Related Sites

  • redhat.com
  • developers.redhat.com
  • connect.redhat.com
  • cloud.redhat.com

Red Hat legal and privacy links

  • About Red Hat
  • Jobs
  • Events
  • Locations
  • Contact Red Hat
  • Red Hat Blog
  • Inclusion at Red Hat
  • Cool Stuff Store
  • Red Hat Summit
© 2025 Red Hat

Red Hat legal and privacy links

  • Privacy statement
  • Terms of use
  • All policies and guidelines
  • Digital accessibility