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OpenAdvisories
High USN-3586-1 4 CVEs

isc-dhcp vulnerabilities

Published Mar 1, 2018 · Updated Apr 22, 2026

Ecosystem: Ubuntu

Summary

Konstantin Orekhov discovered that the DHCP server incorrectly handled a
large number of concurrent TCP sessions. A remote attacker could possibly
use this issue to cause a denial of service. This issue only affected
Ubuntu 14.04 LTS and Ubuntu 16.04 LTS. (CVE-2016-2774)

It was discovered that the DHCP server incorrectly handled socket
descriptors. A remote attacker could possibly use this issue to cause a
denial of service. (CVE-2017-3144)

Felix Wilhelm discovered that the DHCP client incorrectly handled certain
malformed responses. A remote attacker could use this issue to cause the
DHCP client to crash, resulting in a denial of service, or possibly execute
arbitrary code. In the default installation, attackers would be isolated by
the dhclient AppArmor profile. (CVE-2018-5732)

Felix Wilhelm discovered that the DHCP server incorrectly handled reference
counting. A remote attacker could possibly use this issue to cause the DHCP
server to crash, resulting in a denial of service. (CVE-2018-5733)

Fixed packages 2

ReleasePackageFixed in
Ubuntu · 14.04 LTS 14.04:LTS isc-dhcp 4.2.4-7ubuntu12.12
Ubuntu · 16.04 LTS 16.04:LTS isc-dhcp 4.3.3-5ubuntu12.9

Vulnerabilities 4

  • High 7.5
    CVE-2018-5732

    A specially constructed response from a malicious server can cause a buffer overflow in dhclient

    Failure to properly bounds-check a buffer used for processing DHCP options allows a malicious server (or an entity masquerading as a server) to cause a buffer overflow (and resulting crash) in dhclient by sending a response containing a specially constructed …

    ISC ISC DHCP isc-dhcp isc-dhcp Debian Ubuntu Alpine
  • Medium 5.9
    CVE-2018-5733 EPSS 20%

    A malicious client can overflow a reference counter in ISC dhcpd

    A malicious client which is allowed to send very large amounts of traffic (billions of packets) to a DHCP server can eventually overflow a 32-bit reference counter, potentially causing dhcpd to crash. Affects ISC DHCP 4.1.0 -> 4.1-ESV-R15, 4.2.0 -> 4.2.8, 4.3…

    ISC ISC DHCP isc-dhcp isc-dhcp Debian Ubuntu Alpine
  • Medium 5.3
    CVE-2017-3144 EPSS 73%

    Failure to properly clean up closed OMAPI connections can exhaust available sockets

    A vulnerability stemming from failure to properly clean up closed OMAPI connections can lead to exhaustion of the pool of socket descriptors available to the DHCP server. Affects ISC DHCP 4.1.0 to 4.1-ESV-R15, 4.2.0 to 4.2.8, 4.3.0 to 4.3.6. Older versions ma…

    ISC ISC DHCP isc-dhcp isc-dhcp Debian Ubuntu
  • Unscored —
    CVE-2016-2774 EPSS 74%

    ISC DHCP 4.1.x before 4.1-ESV-R13 and 4.2.x and 4.3.x before 4.3.4 does not restrict the number of concurrent TCP sessi…

    isc-dhcp isc-dhcp Debian Ubuntu

References

  • report
    https://ubuntu.com/security/CVE-2016-2774
  • report
    https://ubuntu.com/security/CVE-2017-3144
  • report
    https://ubuntu.com/security/CVE-2018-5732
  • report
    https://ubuntu.com/security/CVE-2018-5733