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.
CVSS Details
- CVSS 3.1 Base Score: 3.7
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alma_linux | — | Upgrade dnsmasq-utilsUpgrade dnsmasq | May 4, 2022 | Jan 20, 2021 |
| Alpine Linux | — | Upgrade dnsmasq | Aug 22, 2024 | Jan 20, 2021 |
| Amazon Linux Ami 2 | — | Upgrade dnsmasqUpgrade dnsmasq-debuginfoUpgrade dnsmasq-utils | Jan 27, 2021 | Jan 20, 2021 |
| Arch Linux | — | Upgrade to the latest version of Arch Linux | Jul 11, 2025 | Jan 20, 2021 |
| Arista Eos | — | Upgrade to a remediated EOS version | Sep 4, 2024 | Jan 19, 2021 |
| Centos_linux | — | Upgrade dnsmasq-utils-debuginfoUpgrade dnsmasq-debugsourceUpgrade dnsmasq-utilsUpgrade dnsmasqUpgrade dnsmasq-debuginfo | Jan 20, 2021 | Jan 19, 2021 |
| Debian | — | Upgrade dnsmasq | Feb 4, 2021 | Jan 20, 2021 |
| Freebsd | — | Upgrade dnsmasqUpgrade dnsmasq-devel | Jan 21, 2021 | Jan 20, 2021 |
| Gentoo Linux | — | Upgrade net-dns/dnsmasq. | Jan 25, 2021 | Jan 20, 2021 |
| Huawei Euleros 2_0_sp2 | — | Upgrade dnsmasqUpgrade dnsmasq-utils | Feb 22, 2021 | Jan 20, 2021 |
| Huawei Euleros 2_0_sp3 | — | Upgrade dnsmasqUpgrade dnsmasq-utils | Feb 22, 2021 | Jan 20, 2021 |
| Huawei Euleros 2_0_sp5 | — | Upgrade dnsmasq-utilsUpgrade dnsmasq | Mar 24, 2021 | Jan 20, 2021 |
| Huawei Euleros 2_0_sp8 | — | Upgrade dnsmasq-utilsUpgrade dnsmasq | Feb 2, 2021 | Jan 20, 2021 |
| Huawei Euleros 2_0_sp9 | — | Upgrade dnsmasq | Feb 8, 2021 | Jan 20, 2021 |
| Nutanix Ahv | — | Upgrade Nutanix AHV to the latest version | Jun 5, 2026 | Aug 24, 2022 |
| Oracle Solaris | — | Upgrade service/network/dnsmasq to version 2.84-11.4.31.0.1.88.1 on Solaris 11.4 | Mar 17, 2021 | Jan 20, 2021 |
| Oracle_linux | — | Upgrade dnsmasq-utilsUpgrade dnsmasq | Jan 20, 2021 | Jan 19, 2021 |
| Qnap Qts | — | Upgrade QNAP QTS to the latest version | Aug 4, 2025 | Jul 1, 2021 |
| Redhat Openshift | — | Upgrade redhat-coreos | Mar 12, 2021 | Jan 20, 2021 |
| Redhat_linux | — | Upgrade dnsmasqUpgrade dnsmasq-debugsourceUpgrade dnsmasq-utils-debuginfoNo solution existsUpgrade dnsmasq-debuginfoUpgrade dnsmasq-utils | Jan 20, 2021 | Jan 19, 2021 |
| Suse | — | Upgrade dnsmasq-utilsUpgrade dnsmasq | Jan 21, 2021 | Jan 19, 2021 |
| Ubuntu | — | Upgrade dnsmasqUpgrade dnsmasq-utilsUpgrade dnsmasq-base | Jan 20, 2021 | Jan 19, 2021 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | Jan 20, 2025 | Jan 20, 2021 |
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