SB2019121626 - Denial of service in knot-resolver
Published: December 16, 2019 Updated: August 3, 2020
Security Bulletin ID
SB2019121626
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Resource management error (CVE-ID: CVE-2019-19331)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
knot-resolver before version 4.3.0 is vulnerable to denial of service through high CPU utilization. DNS replies with very many resource records might be processed very inefficiently, in extreme cases taking even several CPU seconds for each such uncached message. For example, a few thousand A records can be squashed into one DNS message (limit is 64kB).
Remediation
Install update from vendor's website.