CVE-2018-5733: A malicious client can overflow a reference counter in ISC dhcpd
mcnally at isc.org
Wed Feb 28 17:19:40 UTC 2018
Document Version: 1.0
Posting date: 28 February 2018
Program Impacted: DHCP
Versions affected: 4.1.0 -> 4.1-ESV-R15, 4.2.0 -> 4.2.8,
4.3.0 -> 4.3.6, 4.4.0
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
Successful exploitation of this vulnerability may exhaust the
memory available to dhcpd and/or cause it to crash, resulting
in a denial of service to clients.
CVSS Score: 5.9
CVSS Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
For more information on the Common Vulnerability Scoring System and
to obtain your specific environmental score please visit:
Active exploits: No known active exploits.
Upgrade to the patched release most closely related to your
current version of DHCP.
- DHCP 4.1-ESV-R15-P1
- DHCP 4.3.6-P1
- DHCP 4.4.1
ISC would like to thank Felix Wilhelm, Google Security Team, for
reporting this vulnerability.
Document Revision History:
1.0 Advance Notification 21 February 2018
2.0 Public Disclosure 28 February 2018
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which versions are actively supported, please see
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