ISC DHCP < 4.4.2-P1 DoS

high Nessus Plugin ID 150053
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The DHCP server installed on the remote Linux host is affected by a denial of service vulnerability.


The ISC DHCP server installed on the remote host is prior to 4.4.2-P1. It is, therefore, vulnerable to a a buffer overwrite possible when parsing hexadecimal literals with more than 1024 octets. An attacker could exploit this to cause the DHCP server to crash.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.


Upgrade the affected DHCP server to version 4.4.2-P1 or later.

Plugin Details

Severity: High

ID: 150053

File Name: isc_dhcp_cve-2021-25217.nasl

Version: 1.5

Type: local

Agent: unix

Family: Misc.

Published: 5/28/2021

Updated: 10/25/2021

Dependencies: dhcp_detect.nbin

Risk Information

CVSS Score Source: CVE-2021-25217


Risk Factor: Medium

Score: 5.2


Risk Factor: Low

Base Score: 3.3

Temporal Score: 2.4

Vector: AV:A/AC:L/Au:N/C:N/I:N/A:P

Temporal Vector: E:U/RL:OF/RC:C


Risk Factor: High

Base Score: 7.4

Temporal Score: 6.4

Vector: CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:isc:dhcp

Required KB Items: dhcp_server/type, dhcp_server/version

Exploit Ease: No known exploits are available

Patch Publication Date: 5/26/2021

Vulnerability Publication Date: 5/26/2021

Reference Information

CVE: CVE-2021-25217

IAVB: 2021-B-0032