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.
| Version | Base score | Base severity | Vector |
|---|
| CAPEC ID | Description |
|---|
| Event | Date |
|---|
| Hyperlink | Resource |
|---|---|
| https://www.jsof-tech.com/disclosures/dnspooq/ | x_refsource_MISC |
| https://bugzilla.redhat.com/show_bug.cgi?id=1890125 | x_refsource_MISC |
| https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WYW3IR6APUSKOYKL5FT3ACTIHWHGQY32/ | vendor-advisory x_refsource_FEDORA |
| https://security.gentoo.org/glsa/202101-17 | vendor-advisory x_refsource_GENTOO |
| https://www.debian.org/security/2021/dsa-4844 | vendor-advisory x_refsource_DEBIAN |
| https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGB7HL3OWHTLEPSMLDGOMXQKG3KM2QME/ | vendor-advisory x_refsource_FEDORA |
| https://www.arista.com/en/support/advisories-notices/security-advisories/12135-security-advisory-61 | x_refsource_MISC |
| Version | Base score | Base severity | Vector |
|---|
| CAPEC ID | Description |
|---|
| Event | Date |
|---|
| Hyperlink | Resource |
|---|---|
| https://www.jsof-tech.com/disclosures/dnspooq/ | x_refsource_MISC x_transferred |
| https://bugzilla.redhat.com/show_bug.cgi?id=1890125 | x_refsource_MISC x_transferred |
| https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WYW3IR6APUSKOYKL5FT3ACTIHWHGQY32/ | vendor-advisory x_refsource_FEDORA x_transferred |
| https://security.gentoo.org/glsa/202101-17 | vendor-advisory x_refsource_GENTOO x_transferred |
| https://www.debian.org/security/2021/dsa-4844 | vendor-advisory x_refsource_DEBIAN x_transferred |
| https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGB7HL3OWHTLEPSMLDGOMXQKG3KM2QME/ | vendor-advisory x_refsource_FEDORA x_transferred |
| https://www.arista.com/en/support/advisories-notices/security-advisories/12135-security-advisory-61 | x_refsource_MISC x_transferred |
| https://www.kb.cert.org/vuls/id/434904 | N/A |