CVE-2020-25683

Publication date 19 January 2021

Last updated 24 July 2024


Ubuntu priority

Cvss 3 Severity Score

5.9 · Medium

Score breakdown

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.

Status

Package Ubuntu Release Status
dnsmasq 24.10 oracular
Fixed 2.82-1ubuntu2
24.04 LTS noble
Fixed 2.82-1ubuntu2
23.10 mantic
Fixed 2.82-1ubuntu2
23.04 lunar
Fixed 2.82-1ubuntu2
22.10 kinetic
Fixed 2.82-1ubuntu2
22.04 LTS jammy
Fixed 2.82-1ubuntu2
21.10 impish
Fixed 2.82-1ubuntu2
21.04 hirsute
Fixed 2.82-1ubuntu2
20.10 groovy
Fixed 2.82-1ubuntu1.1
20.04 LTS focal
Fixed 2.80-1.1ubuntu1.2
18.04 LTS bionic
Fixed 2.79-1ubuntu0.2
16.04 LTS xenial
Fixed 2.75-1ubuntu0.16.04.7
14.04 LTS trusty
Needs evaluation

Severity score breakdown

Parameter Value
Base score 5.9 · Medium
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact High
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H