OTX Threat: QuartzLine: A working PDF viewer with a backdoor inside

QuartzLine, also tracked as CLOUDHAZE by Mandiant, is malicious software disguised as a functional Windows PDF viewer that conceals a backdoor enabling attackers to execute commands and deploy additional malware. The malware has appeared as paperline.exe and fielddesk.exe, signed with a legitimate but now-revoked EV code-signing certificate. Distribution occurs through malicious advertising, where