Rapid7 Vulnerability & Exploit Database

FreeBSD: VID-5B5CF6E5-5B51-11EB-95AC-7F9491278677 (CVE-2020-25683): dnsmasq -- DNS cache poisoning, and DNSSEC buffer overflow, vulnerabilities

Free InsightVM Trial No Credit Card Necessary
Watch Demo See how it all works
Back to Search

FreeBSD: VID-5B5CF6E5-5B51-11EB-95AC-7F9491278677 (CVE-2020-25683): dnsmasq -- DNS cache poisoning, and DNSSEC buffer overflow, vulnerabilities

Severity
7
CVSS
(AV:N/AC:M/Au:N/C:N/I:N/A:C)
Published
09/16/2020
Created
01/22/2021
Added
01/21/2021
Modified
03/08/2021

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.

Solution(s)

  • freebsd-upgrade-package-dnsmasq
  • freebsd-upgrade-package-dnsmasq-devel

References

  • CVE-2020-25683
  • USN-4698-1

insightVM

Advanced vulnerability management analytics and reporting.
Key Features
Free InsightVM Trial View All Features

With Rapid7 live dashboards, I have a clear view of all the assets on my network, which ones can be exploited, and what I need to do in order to reduce the risk in my environment in real-time. No other tool gives us that kind of value and insight.

– Scott Cheney, Manager of Information Security, Sierra View Medical Center

;