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CVE-2018-5733

A malicious client can overflow a reference counter in ISC dhcpd

Published: Jan 16, 2019Updated: Apr 25, 2025 Sources: CVE List NVD BDUCWE-190
7.5HIGH
NVD MITRE
EPSS Score
20.2%
Top 2.8%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-190

Affected Products

ISC
commercial·USaka internet systems consortium
ISC DHCP
Networking Infrastructure
dhcp
Networking Infrastructure
Red Hat Inc.
commercial·USaka redhat, red hat
Red Hat Enterprise LinuxOn-premOS
Operating Systems / linux-distro
Canonical Ltd.
commercial·GBaka canonical
UbuntuOn-premOS
Operating Systems / linux-distro
debian
oss-project·GBaka debian gnu/linux
debian linuxOn-premOS
Operating Systems / linux-distro
Fedora Project
oss-project·USaka fedora
FedoraOn-premOS
Operating Systems / linux-distro
Internet Systems Consortium
oss-project·USaka isc
dhcpcdOn-prem
Networking Infrastructure / dns-dhcp-ntp
and 9 more affected products View all →

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Initial Access
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References

https://kb.isc.org/docs/aa-01567
kb.isc.org
https://access.redhat.com/errata/RHSA-2018:0469
access.redhat.com
https://www.debian.org/security/2018/dsa-4133
debian.org
and 14 more references View all →

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