TeleMessage TM SGNL
The TeleMessage archiving backend through 2025-05-05 holds cleartext copies of messages from TM SGNL (aka Archive Signal) app users, which is different functionality than described in the TeleMessage "End-to-End encryption from the mobile phone through to the corporate archive" documentation, as exploited in the wild in May 2025.
CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog.