CVE-2020-10995
An issue in the DNS protocol has been found that allow malicious parties to use recursive DNS services to attack third party authoritative name servers.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (4.37%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
PowerDNS Recursor from 4.1.0 up to and including 4.3.0 does not sufficiently defend against amplification attacks. An issue in the DNS protocol has been found that allow malicious parties to use recursive DNS services to attack third party authoritative name servers. The attack uses a crafted reply by an authoritative name server to amplify the resulting traffic between the recursive and other authoritative name servers. Both types of service can suffer degraded performance as an effect. This is triggered by random subdomains in the NSDNAME in NS records. PowerDNS Recursor 4.1.16, 4.2.2 and 4.3.1 contain a mitigation to limit the impact of this DNS protocol issue.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 4.37% probability · 91th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-400
- Affected
- powerdns/recursor · fedoraproject/fedora · debian/debian linux · opensuse/backports sle · opensuse/leap
- Source
- cve@mitre.org
References
- http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00052.htmlMailing List, Third Party Advisory
- http://www.nxnsattack.comTechnical Description, Third Party Advisory
- https://doc.powerdns.com/recursor/security-advisories/powerdns-advisory-2020-01.htmlVendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NMP72NJGKBWR5WEBXAWX5KSLQUDFTG6S/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PS4ZN5XGENYNFKX7QIIOUCQQHXE37GJF/
- https://www.debian.org/security/2020/dsa-4691Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00052.htmlMailing List, Third Party Advisory
- http://www.nxnsattack.comTechnical Description, Third Party Advisory
- https://doc.powerdns.com/recursor/security-advisories/powerdns-advisory-2020-01.htmlVendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NMP72NJGKBWR5WEBXAWX5KSLQUDFTG6S/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PS4ZN5XGENYNFKX7QIIOUCQQHXE37GJF/
- https://www.debian.org/security/2020/dsa-4691Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.