asterisk is vulnerable to Denial of Service.An attacker is able to exploit the vulnerability by sending a malicious unsupported media format packet.
packetstormsecurity.com/files/163639/Asterisk-Project-Security-Advisory-AST-2021-008.html
seclists.org/fulldisclosure/2021/Jul/49
downloads.asterisk.org/pub/security/AST-2021-008.html
issues.asterisk.org/jira/browse/ASTERISK-29392
lists.debian.org/debian-lts-announce/2021/08/msg00005.html
security-tracker.debian.org/tracker/CVE-2021-32558
www.debian.org/security/2021/dsa-4999