CVE-2020-25684 (GCVE-0-2020-25684)

Vulnerability from cvelistv5 – Published: 2021-01-20 15:22 – Updated: 2025-11-04 19:12
VLAI
Summary
A flaw was found in dnsmasq before version 2.83. When getting a reply from a forwarded query, dnsmasq checks in the forward.c:reply_query() if the reply destination address/port is used by the pending forwarded queries. However, it does not use the address/port to retrieve the exact forwarded query, substantially reducing the number of attempts an attacker on the network would have to perform to forge a reply and get it accepted by dnsmasq. This issue contrasts with RFC5452, which specifies a query's attributes that all must be used to match a reply. This flaw allows an attacker to perform a DNS Cache Poisoning attack. If chained with CVE-2020-25685 or CVE-2020-25686, the attack complexity of a successful attack is reduced. The highest threat from this vulnerability is to data integrity.
Severity
No CVSS data available.
CWE
Assigner
References
Impacted products
Vendor Product Version
n/a dnsmasq Affected: dnsmasq 2.83
Show details on NVD website
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