A flaw was found in dnsmasq before version 2.83. When receiving a query, dnsmasq does not check for an existing pending request for the same name and forwards a new request. By default, a maximum of 150 pending queries can be sent to upstream servers, so there can be at most 150 queries for the same name. This flaw allows an off-path attacker on the network to substantially reduce the number of attempts that it would have to perform to forge a reply and have it accepted by dnsmasq. This issue is mentioned in the "Birthday Attacks" section of RFC5452. 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.
History

No history.

cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published: 2021-01-20T16:47:17

Updated: 2024-08-04T15:40:36.677Z

Reserved: 2020-09-16T00:00:00

Link: CVE-2020-25686

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Modified

Published: 2021-01-20T17:15:13.000

Modified: 2023-11-07T03:20:22.280

Link: CVE-2020-25686

cve-icon Redhat

Severity : Moderate

Publid Date: 2021-01-19T00:00:00Z

Links: CVE-2020-25686 - Bugzilla