Topic

An update for dhcp is now available for Red Hat Enterprise Linux 7.

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 Dynamic Host Configuration Protocol (DHCP) is a protocol that allows individual devices on an IP network to get their own network configuration information, including an IP address, a subnet mask, and a broadcast address. The dhcp packages provide a relay agent and ISC DHCP service required to enable and administer DHCP on a network.

Security Fix(es):

• dhcp: double-deletion of the released addresses in the dhcpv6 code leading to crash and possible DoS (CVE-2019-6470)

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 7.7 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 Server 7 x86_64
• Red Hat Enterprise Linux Workstation 7 x86_64
• Red Hat Enterprise Linux Desktop 7 x86_64
• Red Hat Enterprise Linux for IBM z Systems 7 s390x
• Red Hat Enterprise Linux for Power, big endian 7 ppc64
• Red Hat Enterprise Linux for Scientific Computing 7 x86_64
• Red Hat Enterprise Linux for Power, little endian 7 ppc64le

Fixes

• BZ - 1574292 - "dhclient -I" shows "cant find device client" after upgrade
• BZ - 1613174 - ISC dhcpd cannot start TLS session to 389-DS after updating openldap rpm
• BZ - 1623792 - /var/lib/dhcpd/dhcpd.leases: file is too long to buffer. is displayed when dhcpd tries to start.
• BZ - 1672308 - Avoid unnecessary DHCPD restarts by NetworkManager on certain UP events w.r.t. bug #565921
• BZ - 1677382 - dhcp does not compile with rebased bind 9.11
• BZ - 1708641 - CVE-2019-6470 dhcp: double-deletion of the released addresses in the dhcpv6 code leading to crash and possible DoS

CVEs

• CVE-2019-6470

References

• https://access.redhat.com/security/updates/classification/#moderate
• https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/7.7_release_notes/index