CVE-2018-5733

A malicious client can overflow a reference counter in ISC dhcpd

HIGH
7.5
CVSS Score
Published: January 16, 2019 at 08:00 PM UTC
Updated: June 17, 2026 at 02:00 AM UTC
8 products affected across 4 vendorsDebian LinuxUbuntu LinuxEnterprise Linux Desktop

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Severity
HIGH7.5
Exploit prediction
EPSS 20%

Description

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, 4.3.0 -> 4.3.6, 4.4.0.

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (10)

VDB Entryx_refsource_BIDThird Party Advisory
http://www.securityfocus.com/bid/103188
VDB Entryx_refsource_SECTRACKThird Party Advisory
http://www.securitytracker.com/id/1040437
Vendor Advisoryx_refsource_REDHATThird Party Advisory
https://access.redhat.com/errata/RHSA-2018:0469
Vendor Advisoryx_refsource_REDHATThird Party Advisory
https://access.redhat.com/errata/RHSA-2018:0483
x_refsource_CONFIRMVendor Advisory
https://kb.isc.org/docs/aa-01567
Mailing Listx_refsource_MLISTThird Party Advisory
https://lists.debian.org/debian-lts-announce/2018/03/msg00015.html
Vendor Advisoryx_refsource_UBUNTUThird Party Advisory
https://usn.ubuntu.com/3586-1/
Vendor Advisoryx_refsource_UBUNTUThird Party Advisory
https://usn.ubuntu.com/3586-2/

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-190

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