AI brand impersonation campaigns exploit ChatGPT, Claude, DeepSeek lures for credential theft and malware
Microsoft Threat Intelligence observed multiple campaigns impersonating popular AI platforms (ChatGPT, Claude, DeepSeek, Copilot) via phishing, malvertising, and SEO attacks to steal credentials, financial data, and deploy malware including Vidar stealer.
Attack Brief
TargetEnterprise and consumer users across multiple sectors including higher education, professional services, and financial servicesVectorPhishing emails with AI brand impersonation, malvertising, SEO-driven attacks, and fake application installers leading to credential theft and malware deploymentAttributionMultiple threat actors including Storm-3075 (initial access broker) and Fox Tempest (financially motivated, malware-signing-as-a-service operator)
Technical Details
IoCsgrupoconstat[.]bitrix24[.]com[.]brawstrack[.]melegendarytrendsbay[.]shopRebrandly URL shortener (abused)AffectedChatGPT Plus subscription lures; Claude-themed campaigns; DeepSeek V4 fake installers on GitHub; Microsoft Copilot; Anthropic Claude
Impact
Affected OrganisationsUnattributed; broad targeting across multiple organizationsSectorsHigher educationProfessional servicesFinancial servicesConfirmed DamageCredit card data theft, personal information collection (names, addresses), credential theft, access token theft, malware infection (Vidar stealer)GeographySouth AfricaSwitzerlandAustria
Mitigation
PatchesMicrosoft Defender for Office 365Microsoft Defender for EndpointMicrosoft Defender for IdentityMicrosoft Defender for Cloud AppsMicrosoft Entra ID ProtectionWorkaroundsOrganizations should leverage AI-powered security capabilities to enhance visibility, automate detection, and accelerate response across email, identity, and endpoint surfaces. Implement multi-stage URL redirection detection and abuse of trusted services monitoring.DetectionMonitor for urgency-driven messaging in emails impersonating AI platforms; detect multi-stage redirection chains through legitimate services (CRM, email tracking, URL shorteners); hunt for Vidar stealer indicators; track malvertising campaigns and SEO-driven attack chains
Context
Previous CampaignsStorm-3075 previously employed malvertising; Fox Tempest operates malware-signing-as-a-service (MSaaS) offering used by multiple downstream actorsSimilar AttacksAI-themed lures represent shift in social engineering tactics from traditional invoice/payment/delivery alerts; campaigns combine longstanding tactics including urgency-driven messaging and abuse of trusted services