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.
Metrics
Affected Vendors & Products
Advisories
Source | ID | Title |
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DLA-2604-1 | dnsmasq security update |
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DSA-4844-1 | dnsmasq security update |
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EUVD-2020-18346 | 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. |
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USN-4698-1 | Dnsmasq vulnerabilities |
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
No history.

Status: PUBLISHED
Assigner: redhat
Published:
Updated: 2024-08-04T15:40:36.670Z
Reserved: 2020-09-16T00:00:00
Link: CVE-2020-25684

No data.

Status : Modified
Published: 2021-01-20T16:15:14.163
Modified: 2024-11-21T05:18:27.603
Link: CVE-2020-25684


No data.