CVE-2020-25683

Published Jan 20, 2021

Last updated a year ago

Overview

Description
A flaw was found in dnsmasq before version 2.83. A heap-based buffer overflow was discovered in dnsmasq when DNSSEC is enabled and before it validates the received DNS entries. A remote attacker, who can create valid DNS replies, could use this flaw to cause an overflow in a heap-allocated memory. This flaw is caused by the lack of length checks in rfc1035.c:extract_name(), which could be abused to make the code execute memcpy() with a negative size in get_rdata() and cause a crash in dnsmasq, resulting in a denial of service. The highest threat from this vulnerability is to system availability.
Source
secalert@redhat.com
NVD status
Modified

Risk scores

CVSS 3.1

Type
Primary
Base score
5.9
Impact score
3.6
Exploitability score
2.2
Vector string
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

CVSS 2.0

Type
Primary
Base score
7.1
Impact score
6.9
Exploitability score
8.6
Vector string
AV:N/AC:M/Au:N/C:N/I:N/A:C

Weaknesses

secalert@redhat.com
CWE-122

Social media

Hype score
Not currently trending

Configurations