CVE-2020-25684
Published: August 31, 2023Last modified: August 31, 2023
Description
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 score breakdown
Parameter | Value |
---|---|
Base score | 3.7 |
Attack Vector | NETWORK |
Attack complexity | HIGH |
Privileges required | NONE |
User interaction | NONE |
Scope | UNCHANGED |
Confidentiality | NONE |
Integrity impact | LOW |
Availability impact | NONE |
Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N |
Status
Product | Release | Package | Status |
---|---|---|---|
Alpaquita Linux | 23 LTS | dnsmasq | Not affected (2.87-r2) |
Stream | dnsmasq | Not affected (2.89-r6) |
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1889686
- https://lists.debian.org/debian-lts-announce/2021/03/msg00027.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGB7HL3OWHTLEPSMLDGOMXQKG3KM2QME/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WYW3IR6APUSKOYKL5FT3ACTIHWHGQY32/
- https://lists.fedoraproject.org/archives/list/[email protected]/message/QGB7HL3OWHTLEPSMLDGOMXQKG3KM2QME/
- https://lists.fedoraproject.org/archives/list/[email protected]/message/WYW3IR6APUSKOYKL5FT3ACTIHWHGQY32/
- https://security.gentoo.org/glsa/202101-17
- https://www.arista.com/en/support/advisories-notices/security-advisories/12135-security-advisory-61
- https://www.debian.org/security/2021/dsa-4844
- https://www.jsof-tech.com/disclosures/dnspooq/