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:extractname(), which could be abused to make the code execute memcpy() with a negative size in sortrrset() and cause a crash in dnsmasq, resulting in a denial of service. The highest threat from this vulnerability is to system availability.
[
{
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{
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{
"events": [
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{
"events": [
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{
"last_affected": "33"
}
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{
"events": [
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{
"last_affected": "9.0"
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]
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{
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]
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-25687.json"