The TP-240 (aka tp240dvr) component in Mitel MiCollab before 9.4 SP1 FP1 and MiVoice Business Express through 8.1 allows remote attackers to obtain sensitive information and cause a denial of service (performance degradation and excessive outbound traffic). This was exploited in the wild in February and March 2022 for the TP240PhoneHome DDoS attack.
https://www.mitel.com/en-ca/support/security-advisories/mitel-product-security-advisory-22-0001
https://www.akamai.com/blog/security/phone-home-ddos-attack-vector
https://team-cymru.com/blog/2022/03/08/record-breaking-ddos-potential-discovered-cve-2022-26143/
https://news.ycombinator.com/item?id=30614073