CVE-2020-12667

Knot Resolver before 5.1.1 allows traffic amplification via a crafted DNS answer from an attacker-controlled server, aka an "NXNSAttack" issue. This is triggered by random subdomains in the NSDNAME in NS records.

CVSS v3.0 7.5 HIGH
CVSS v2.0 5.0 MEDIUM

7.5^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

5.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:N/C:N/I:N/A:P

Exploitability : 10.0 / Impact : 2.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact PARTIAL

References

Link	Resource
https://en.blog.nic.cz/2020/05/19/nxnsattack-upgrade-resolvers-to-stop-new-kind-of-random-subdomain-attack/	Technical Description Vendor Advisory
https://www.knot-resolver.cz/2020-05-19-knot-resolver-5.1.1.html	Release Notes Vendor Advisory
http://www.openwall.com/lists/oss-security/2020/05/19/2	Mailing List Third Party Advisory
http://cyber-security-group.cs.tau.ac.il/#	Technical Description Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/76Y4FITMOH6RVPWAANGV7NB2ZHPJJGDQ/

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Configurations

Configuration 1 (hide)

cpe:2.3:a:nic:knot_resolver:*:*:*:*:*:*:*:*

Information

Published : 2020-05-19 06:15

Updated : 2020-05-28 00:15

NVD link : CVE-2020-12667

Mitre link : CVE-2020-12667

JSON object : View

CWE

CWE-400

Uncontrolled Resource Consumption

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Products Affected

nic

knot_resolver

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