CVE-2020-12667: High severity nic Knot Resolver vulnerability
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.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/knot-resolverto a version that resolves this vulnerability.Fixed in 5.3.1-1+deb11u1Fixed in 5.6.0-1+deb12u1Fixed in 5.7.4-2 - Upgrade
Upgrade
alpine/knot-resolverto a version that resolves this vulnerability.Fixed in 4.3.0-r3 - Upgrade
Upgrade
alpine/knot-resolverto a version that resolves this vulnerability.Fixed in 5.1.1-r0 - Upgrade
Upgrade
Knot Resolverto a version that resolves this vulnerability.Fixed in 5.1.1
Event History
Frequently Asked Questions
What is CVE-2020-12667?
CVE-2020-12667 is a vulnerability found in Knot Resolver before version 5.1.1.
What is the severity of CVE-2020-12667?
The severity of CVE-2020-12667 is high, with a severity value of 7.5.
How can CVE-2020-12667 be exploited?
CVE-2020-12667 can be exploited through traffic amplification via a crafted DNS answer from an attacker-controlled server.
How can I fix CVE-2020-12667?
To fix CVE-2020-12667, users should upgrade to Knot Resolver version 5.1.1 or later.
Where can I find more information about CVE-2020-12667?
You can find more information about CVE-2020-12667 at the following references: - http://cyber-security-group.cs.tau.ac.il/# - http://www.openwall.com/lists/oss-security/2020/05/19/2 - https://en.blog.nic.cz/2020/05/19/nxnsattack-upgrade-resolvers-to-stop-new-kind-of-random-subdomain-attack/