Oval Definition:oval:com.redhat.rhsa:def:20172836
Revision Date:2017-10-02Version:638
Title:RHSA-2017:2836: dnsmasq security update (Critical)
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)

  • A heap buffer overflow was discovered in dnsmasq in the IPv6 router advertisement (RA) handling code. An attacker on the local network segment could send crafted RAs to dnsmasq which would cause it to crash or, potentially, execute arbitrary code. This issue only affected configurations using one of these options: enable-ra, ra-only, slaac, ra-names, ra-advrouter, or ra-stateless. (CVE-2017-14492)

  • A stack buffer overflow was found in dnsmasq in the DHCPv6 code. An attacker on the local network could send a crafted DHCPv6 request to dnsmasq which would cause it to a crash or, potentially, execute arbitrary code. (CVE-2017-14493)

  • An information leak was found in dnsmasq in the DHCPv6 relay code. An attacker on the local network could send crafted DHCPv6 packets to dnsmasq causing it to forward the contents of process memory, potentially leaking sensitive data. (CVE-2017-14494)

  • A memory exhaustion flaw was found in dnsmasq in the EDNS0 code. An attacker could send crafted DNS packets which would trigger memory allocations which would never be freed, leading to unbounded memory consumption and eventually a crash. This issue only affected configurations using one of the options: add-mac, add-cpe-id, or add-subnet. (CVE-2017-14495)

  • An integer underflow flaw leading to a buffer over-read was found in dnsmasq in the EDNS0 code. An attacker could send crafted DNS packets to dnsmasq which would cause it to crash. This issue only affected configurations using one of the options: add-mac, add-cpe-id, or add-subnet. (CVE-2017-14496)

    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 these issues.
  • Family:unixClass:patch
    Status:Reference(s):CVE-2017-14491
    CVE-2017-14492
    CVE-2017-14493
    CVE-2017-14494
    CVE-2017-14495
    CVE-2017-14496
    RHSA-2017:2836
    RHSA-2017:2836-00
    RHSA-2017:2836-01
    Platform(s):Red Hat Enterprise Linux 7
    Product(s):
    Definition Synopsis
  • Red Hat Enterprise Linux must be installed
  • OR Package Information
  • Red Hat Enterprise Linux 7 is installed
  • AND
  • dnsmasq is earlier than 0:2.76-2.el7_4.2
  • AND dnsmasq is signed with Red Hat redhatrelease2 key
  • dnsmasq-utils is earlier than 0:2.76-2.el7_4.2
  • AND dnsmasq-utils is signed with Red Hat redhatrelease2 key
  • BACK