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Red Hat: CVE-2020-25687: CVE-2020-25687 dnsmasq: heap-based buffer overflow with large memcpy in sort_rrset() when DNSSEC is enabled (Multiple Advisories)

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Red Hat: CVE-2020-25687: CVE-2020-25687 dnsmasq: heap-based buffer overflow with large memcpy in sort_rrset() when DNSSEC is enabled (Multiple Advisories)

Severity
7
CVSS
(AV:N/AC:M/Au:N/C:N/I:N/A:C)
Published
01/19/2021
Created
01/20/2021
Added
01/20/2021
Modified
12/15/2023

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. This flaw allows a remote attacker, who can create valid DNS replies, 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 sort_rrset() and cause a crash in dnsmasq, resulting in a denial of service. The highest threat from this vulnerability is to system availability.

Solution(s)

  • redhat-upgrade-dnsmasq
  • redhat-upgrade-dnsmasq-debuginfo
  • redhat-upgrade-dnsmasq-debugsource
  • redhat-upgrade-dnsmasq-utils
  • redhat-upgrade-dnsmasq-utils-debuginfo

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