CVE-2018-5732

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

Description

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

Remediation

Solution:

  • 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

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 3.0 •
CVSS 2.0 •
EPSS 2.35% Top 20%
Vendor Advisory isc.org
Affected: ISC ISC DHCP
Published at:
Updated at:

References

Link Tags
https://kb.isc.org/docs/aa-01565 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2018-5732?
CVE-2018-5732 has been scored as a high severity vulnerability.
How to fix CVE-2018-5732?
To fix CVE-2018-5732: 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
Is CVE-2018-5732 being actively exploited in the wild?
It is possible that CVE-2018-5732 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2018-5732?
CVE-2018-5732 affects ISC ISC DHCP.
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