system
Provide references for <CVE-2020-21839>.
user
Where can I find more information about <CVE-2020-21839>?
assistant
References are available at: http://gnu.com, https://github.com/LibreDWG/libredwg/issues/188#issuecomment-574492707, https://cwe.mitre.org/data/definitions/401.html.