Adversaries may use voice communications to ultimately gain access to victim systems. Spearphishing voice is a specific variant of spearphishing. It is different from other forms of spearphishing in that it employs the use of manipulating a user into providing access to systems through a phone call or other forms of voice communications. Spearphishing frequently involves social engineering techniques, such as posing as a trusted source (ex: Impersonation) and/or creating a sense of urgency or alarm for the recipient. All forms of phishing are electronically delivered social engineering. In this scenario, adversaries are not directly sending malware to a victim vice relying on User Execution for delivery and execution. For example, victims may receive phishing messages that instruct them to call a phone number where they are directed to visit a malicious URL, download malware,(Citation: sygnia Luna Month)(Citation: CISA Remote Monitoring and Management Software) or install adversary-accessible remote management tools (Remote Access Tools) onto their computer.(Citation: Unit42 Luna Moth) Adversaries may also combine voice phishing with Multi-Factor Authentication Request Generation in order to trick users into divulging MFA credentials or accepting authentication prompts.(Citation: Proofpoint Vishing)
Correlate MFA push fatigue or unusual consent grant attempts with call activity where adversaries may have socially engineered the user over voice.
Monitor Facetime, iMessage, or SIP client logs for anomalous voice call attempts. Link to subsequent user execution events (downloads, RMM installs) triggered post-call.
Audit VoIP/SIP logs for suspicious outbound calls or call setup messages to unusual endpoints. Correlate with user activity such as browser execution or package installation following the call.