RHSA-2017:2840 - Security Advisory

Topic

An update for dnsmasq is now available for Red Hat Enterprise Linux 5 Extended Lifecycle Support.

Red Hat Product Security has rated this update as having a security impact of Critical. 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):

• A heap buffer overflow was found in dnsmasq in the code responsible for building DNS replies. An attacker could send crafted DNS packets to dnsmasq which would cause it to crash or, potentially, execute arbitrary code. (CVE-2017-14491)

Red Hat would like to thank Felix Wilhelm (Google Security Team), Fermin J. Serna (Google Security Team), Gabriel Campana (Google Security Team), Kevin Hamacher (Google Security Team), and Ron Bowes (Google Security Team) for reporting this issue.

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 Server 5 x86_64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 5 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 5 s390x

Fixes

• BZ - 1495409 - CVE-2017-14491 dnsmasq: heap overflow in the code responsible for building DNS replies

CVEs

• CVE-2017-14491

References

• https://access.redhat.com/security/updates/classification/#critical
• https://access.redhat.com/security/vulnerabilities/3199382