Input validation error in Knot Resolver - CVE-2019-10190
Published: July 16, 2019 / Updated: July 17, 2020
Vulnerability identifier: #VU30985
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2019-10190
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote non-authenticated attacker to manipulate data.
A vulnerability was discovered in DNS resolver component of knot resolver through version 3.2.0 before 4.1.0 which allows remote attackers to bypass DNSSEC validation for non-existence answer. NXDOMAIN answer would get passed through to the client even if its DNSSEC validation failed, instead of sending a SERVFAIL packet. Caching is not affected by this particular bug but see CVE-2019-10191.
Affected software
Knot Resolver
knot-resolver (Alpine package)
knot
knot-resolver (Ubuntu package)
knot-resolver
Fedora
Ubuntu
knot-resolver (Alpine package)
knot
knot-resolver (Ubuntu package)
knot-resolver
Fedora
Ubuntu
How to mitigate CVE-2019-10190
Install update from vendor's website.
Knot Resolver - update to 4.1.0
knot-resolver (Alpine package) - update to 4.1.0-r0
knot - update to 2.8.2-1.el7
knot-resolver (Ubuntu package) - update to 3.2.1-3ubuntu2.2
knot-resolver - addressed in versions 4.1.0-1.el7, 4.1.0-1.fc29, 4.1.0-1.fc30
knot-resolver (Alpine package) - update to 4.1.0-r0
knot - update to 2.8.2-1.el7
knot-resolver (Ubuntu package) - update to 3.2.1-3ubuntu2.2
knot-resolver - addressed in versions 4.1.0-1.el7, 4.1.0-1.fc29, 4.1.0-1.fc30
External References
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-10190
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TMSSWBHINIX4WE6UDXWM66L7JYEK6XS6/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VZV5YZZ5766UIG2TFLFJL6EESQNAP5X5/
- https://www.knot-resolver.cz/2019-07-10-knot-resolver-4.1.0.html