CVE-2018-5732: A specially constructed response from a malicious server can cause a buffer overflow in dhclient

Published Feb 28, 2018
·
Updated

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 options section.

Versions of DHCP affected: 4.1.0 -> 4.1-ESV-R15, 4.2.0 -> 4.2.8, 4.3.0 -> 4.3.6, 4.4.0

Other sources

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 options section. Affects ISC DHCP versions 4.1.0 -> 4.1-ESV-R15, 4.2.0 -> 4.2.8, 4.3.0 -> 4.3.6, 4.4.0

Launchpad

Affected Software

42 affected componentsFixes available
redhat/dhcp<4.1
4.1
redhat/dhcp<4.3.6
4.3.6
redhat/dhcp<4.4.1
4.4.1
ISC DHCP>=4.1.0<=4.1.2
ISC DHCP>=4.2.0<4.2.8
ISC DHCP>=4.3.0<4.3.6
ISC DHCP=4.1-esv
ISC DHCP=4.1-esv-r1
ISC DHCP=4.1-esv-r10
ISC DHCP=4.1-esv-r10b1
ISC DHCP=4.1-esv-r10rc1
ISC DHCP=4.1-esv-r11
ISC DHCP=4.1-esv-r11b1
ISC DHCP=4.1-esv-r11rc1
ISC DHCP=4.1-esv-r11rc2
ISC DHCP=4.1-esv-r12
ISC DHCP=4.1-esv-r12-p1
ISC DHCP=4.1-esv-r12b1
ISC DHCP=4.1-esv-r13
ISC DHCP=4.1-esv-r13b1
ISC DHCP=4.1-esv-r14
ISC DHCP=4.1-esv-r14b1
ISC DHCP=4.1-esv-r15
ISC DHCP=4.1-esv-r2
ISC DHCP=4.1-esv-r3
ISC DHCP=4.1-esv-r3b1
ISC DHCP=4.1-esv-r4
ISC DHCP=4.1-esv-r5
ISC DHCP=4.1-esv-r5b1
ISC DHCP=4.1-esv-r5rc1
ISC DHCP=4.1-esv-r5rc2
ISC DHCP=4.1-esv-r6
ISC DHCP=4.1-esv-r7
ISC DHCP=4.1-esv-r8
ISC DHCP=4.1-esv-r8b1
ISC DHCP=4.1-esv-r8rc1
ISC DHCP=4.1-esv-r9
ISC DHCP=4.1-esv-r9b1
ISC DHCP=4.1-esv-r9rc1
ISC DHCP=4.1.2-p1
ISC DHCP=4.4.0
debian/isc-dhcp
4.4.1-2.3+deb11u24.4.1-2.3+deb11u14.4.3-P1-24.4.3-P1-8

Remediation

Information

Upgrade to the patched release most closely related to your current version of DHCP. ISC DHCP releases are available from https://www.isc.org/downloads. >= DHCP 4.1-ESV-R15-P1 >= DHCP 4.3.6-P1 >= DHCP 4.4.1

Event History

Feb 28, 2018
Data Sourced
08:45 PM
SeverityAffected Software
Oct 9, 2019
CVE Published
via MITRE·02:17 PM
Data Sourced
via MITRE·02:17 PM
RemedyDescriptionSeverityWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:07 PM
Description
Feb 19, 2026
Data Sourced
via Ubuntu·04:50 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Debian·04:50 PM
DescriptionAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2018-5732?

The severity of CVE-2018-5732 is high with a CVSS score of 7.5.

2

How does CVE-2018-5732 affect ISC DHCP?

CVE-2018-5732 affects ISC DHCP versions 4.1.0 to 4.1.2, 4.2.0 to 4.2.8, and 4.3.0 to 4.3.6.

3

How does CVE-2018-5732 impact Ubuntu?

Ubuntu versions 12.04 LTS (Precise Pangolin), 14.04 LTS (Trusty Tahr), 16.04 LTS (Xenial Xerus), and 18.04 LTS (Bionic Beaver) are affected by CVE-2018-5732 in the ISC DHCP package.

4

How does CVE-2018-5732 impact Red Hat?

Red Hat is affected by CVE-2018-5732 in the dhcp package versions 4.1, 4.3.6, and 4.4.1.

5

What is the Common Weakness Enumeration (CWE) of CVE-2018-5732?

The CWE of CVE-2018-5732 is CWE-119, which refers to Improper Restriction of Operations within the Bounds of a Memory Buffer.

Contact

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