CVE-2020-12667
published 2020-05-19CVE-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…
PriorityP340high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
2.62%
83.6th percentile
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
7 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cz.nic | knot-resolver | >= 0 < 5.1.1-0.1 | 5.1.1-0.1 |
| cz.nic | knot-resolver | >= 0 < 5.1.1-0.1 | 5.1.1-0.1 |
| cz.nic | knot-resolver | >= 0 < 5.1.1-0.1 | 5.1.1-0.1 |
| cz.nic | knot-resolver | >= 0 < 5.1.1-0.1 | 5.1.1-0.1 |
| cz.nic | knot-resolver | >= 0 < 3.2.1-3ubuntu2.2 | 3.2.1-3ubuntu2.2 |
| debian | knot-resolver | < knot-resolver 5.1.1-0.1 (bookworm) | knot-resolver 5.1.1-0.1 (bookworm) |
| nic | knot_resolver | < 5.1.1 | 5.1.1 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
osv7.5HIGH
vendor_debian7.5HIGH
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OSV
knot-resolver vulnerabilities
osv·2024-10-01·CVSS 7.5
CVE-2019-10190 [HIGH] knot-resolver vulnerabilities
knot-resolver vulnerabilities
Vladimír Čunát discovered that Knot Resolver incorrectly handled input
during DNSSEC validation. A remote attacker could possibly use this issue
to bypass certain validations. (CVE-2019-10190)
Vladimír Čunát discovered that Knot Resolver incorrectly handled input
during DNSSEC validation. A remote attacker could possibly use this issue
to downgrade DNSSEC-secure domains to a DNSSEC-insecure state, resulting
in a domain hijacking attack. (CVE-2019-10191)
Vladimír Čunát discovered that Knot Resolver incorrectly handled certain
DNS replies with many resource records. An attacker could possibly use
this issue to consume system resources, resulting in a denial of service.
(CVE-2019-19331)
Lior Shafir, Yehuda Afek, and Anat Bremler-Barr discovered that Knot
Reso
GHSA
GHSA-2gpj-6wgq-8636: Knot Resolver before 5
ghsa_unreviewed·2022-05-24
CVE-2020-12667 [MEDIUM] CWE-400 GHSA-2gpj-6wgq-8636: Knot Resolver before 5
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.
OSV
CVE-2020-12667: Knot Resolver before 5
osv·2020-05-19·CVSS 7.5
CVE-2020-12667 [HIGH] CVE-2020-12667: Knot Resolver before 5
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.
Debian
CVE-2020-12667: knot-resolver - Knot Resolver before 5.1.1 allows traffic amplification via a crafted DNS answer...
vendor_debian·2020·CVSS 7.5
CVE-2020-12667 [HIGH] CVE-2020-12667: knot-resolver - Knot Resolver before 5.1.1 allows traffic amplification via a crafted DNS answer...
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.
Scope: local
bookworm: resolved (fixed in 5.1.1-0.1)
bullseye: resolved (fixed in 5.1.1-0.1)
forky: resolved (fixed in 5.1.1-0.1)
sid: resolved (fixed in 5.1.1-0.1)
trixie: resolved (fixed in 5.1.1-0.1)
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2020-12667 knot-resolver: Traffic amplification triggered by random subdomains in the NSDNAME in NS records [fedora-all]
bugzilla·2020-05-25·CVSS 7.5
CVE-2020-12667 [HIGH] CVE-2020-12667 knot-resolver: Traffic amplification triggered by random subdomains in the NSDNAME in NS records [fedora-all]
CVE-2020-12667 knot-resolver: Traffic amplification triggered by random subdomains in the NSDNAME in NS records [fedora-all]
This is an automatically created tracking bug! It was created to ensure
that one or more security vulnerabilities are fixed in affected versions
of fedora-all.
For comments that are specific to the vulnerability please use bugs filed
against the "Security Response" product referenced in the "Blocks" field.
For more information see:
http://fedoraproject.org/wiki/Security/TrackingBugs
When submitting as an update, use the fedpkg template provided in the next
comment(s). This will include the bug IDs of this tracking bug as well as
the relevant top-level CVE bugs.
Please also mention the CVE IDs being fixed in the RPM changelog and the
fedpkg commit message.
NOTE:
Bugzilla
CVE-2020-12667 knot-resolver: Traffic amplification triggered by random subdomains in the NSDNAME in NS records [epel-7]
bugzilla·2020-05-25·CVSS 7.5
CVE-2020-12667 [HIGH] CVE-2020-12667 knot-resolver: Traffic amplification triggered by random subdomains in the NSDNAME in NS records [epel-7]
CVE-2020-12667 knot-resolver: Traffic amplification triggered by random subdomains in the NSDNAME in NS records [epel-7]
This is an automatically created tracking bug! It was created to ensure
that one or more security vulnerabilities are fixed in affected versions
of epel-7.
For comments that are specific to the vulnerability please use bugs filed
against the "Security Response" product referenced in the "Blocks" field.
For more information see:
http://fedoraproject.org/wiki/Security/TrackingBugs
When submitting as an update, use the fedpkg template provided in the next
comment(s). This will include the bug IDs of this tracking bug as well as
the relevant top-level CVE bugs.
Please also mention the CVE IDs being fixed in the RPM changelog and the
fedpkg commit message.
Discussion:
Bugzilla
CVE-2020-12667 knot-resolver: Traffic amplification triggered by random subdomains in the NSDNAME in NS records
bugzilla·2020-05-25·CVSS 7.5
CVE-2020-12667 [HIGH] CVE-2020-12667 knot-resolver: Traffic amplification triggered by random subdomains in the NSDNAME in NS records
CVE-2020-12667 knot-resolver: Traffic amplification triggered by random subdomains in the NSDNAME in NS records
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.
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/
https://www.knot-resolver.cz/2020-05-19-knot-resolver-5.1.1.html
Discussion:
Created knot-resolver tracking bugs for this issue:
Affects: epel-7 [bug 1839823]
Affects: fedora-all [bug 1839822]
---
This CVE Bugzilla entry is for community support in
http://cyber-security-group.cs.tau.ac.il/#http://www.openwall.com/lists/oss-security/2020/05/19/2https://en.blog.nic.cz/2020/05/19/nxnsattack-upgrade-resolvers-to-stop-new-kind-of-random-subdomain-attack/https://lists.debian.org/debian-lts-announce/2024/04/msg00017.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/76Y4FITMOH6RVPWAANGV7NB2ZHPJJGDQ/https://www.knot-resolver.cz/2020-05-19-knot-resolver-5.1.1.htmlhttp://cyber-security-group.cs.tau.ac.il/#http://www.openwall.com/lists/oss-security/2020/05/19/2https://en.blog.nic.cz/2020/05/19/nxnsattack-upgrade-resolvers-to-stop-new-kind-of-random-subdomain-attack/https://lists.debian.org/debian-lts-announce/2024/04/msg00017.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/76Y4FITMOH6RVPWAANGV7NB2ZHPJJGDQ/https://www.knot-resolver.cz/2020-05-19-knot-resolver-5.1.1.html
2020-05-19
Published