| Description: | A flaw was found in dnsmasq before version 2.83. When getting a reply
from a forwarded query, dnsmasq checks in forward.c:reply_query(),
which is the forwarded query that matches the reply, by only using a
weak hash of the query name. Due to the weak hash (CRC32 when dnsmasq
is compiled without DNSSEC, SHA-1 when it is) this flaw allows an off-
path attacker to find several different domains all having the same
hash, substantially reducing the number of attempts they would have to
perform to forge a reply and get it accepted by dnsmasq. This is in
contrast with RFC5452, which specifies that the query name is one of
the attributes of a query that must be used to match a reply. This
flaw could be abused to perform a DNS Cache Poisoning attack. If
chained with CVE-2020-25684 the attack complexity of a successful
attack is reduced. The highest threat from this vulnerability is to
data integrity.
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