This fixes the following security problems in dnsmasq:
* CVE-2020-25681:
Dnsmasq versions before 2.83 is susceptible to a heap-based buffer
overflow in sort_rrset() when DNSSEC is used. This can allow a remote
attacker to write arbitrary data into target device's memory that can
lead to memory corruption and other unexpected behaviors on the target
device.
* CVE-2020-25682:
Dnsmasq versions before 2.83 is susceptible to buffer overflow in
extract_name() function due to missing length check, when DNSSEC is
enabled. This can allow a remote attacker to cause memory corruption
on the target device.
* CVE-2020-25683:
Dnsmasq version before 2.83 is susceptible to a heap-based buffer
overflow when DNSSEC is enabled. 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
rtc1035.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.
* CVE-2020-25684:
A lack of proper address/port check implemented in Dnsmasq version <
2.83 reply_query function makes forging replies easier to an off-path
attacker.
* CVE-2020-25685:
A lack of query resource name (RRNAME) checks implemented in Dnsmasq's
versions before 2.83 reply_query function allows remote attackers to
spoof DNS traffic that can lead to DNS cache poisoning.
* CVE-2020-25686:
Multiple DNS query requests for the same resource name (RRNAME) by
Dnsmasq versions before 2.83 allows for remote attackers to spoof DNS
traffic, using a birthday attack (RFC 5452), that can lead to DNS
cache poisoning.
* CVE-2020-25687:
Dnsmasq versions before 2.83 is vulnerable to a heap-based buffer
overflow with large memcpy in sort_rrset() when DNSSEC is enabled. 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 rtc1035.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.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Hauke Mehrtens
8055e38794