SB2019120531 - Resource management error in knot-resolver (Alpine package)



SB2019120531 - Resource management error in knot-resolver (Alpine package)

Published: December 5, 2019

Security Bulletin ID SB2019120531
Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 security 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.