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ASCII smuggling crosses over from AI prompt injection to phishing evasion

Microsoft details high-volume phishing campaign using ASCII smuggling (Unicode tag chars) for filter evasion, peaking at 2.3M messages.

Microsoft researchers observed a high-volume finance-themed phishing campaign using invisible Unicode tag characters (U+E0000–U+E007F), a technique known from AI prompt injection research as ASCII smuggling, to split lure words like 'funding' and evade email filters. Telemetry from Microsoft Defender for Office 365 showed signature hits jump from roughly 21,000 messages on February 8, 2026 to more than 1.3 million on February 9, peaking above 2.3 million on February 11, with elevated weekday activity lasting approximately three months. The discovery emerged from prompt injection protection research, showing AI-era evasion techniques crossing into traditional phishing. Most messages were flagged by layered Defender protections rather than a single Unicode-specific signal.

Microsoft Security Blog · 13d agoPhishing & fraud in the wild1

Hackers Use AI-Assisted CEO Emails to Trick Finance Teams Into Sending $50,000 Payments.

Microsoft tracked a million-message AI-assisted BEC campaign impersonating executives with fake ServiceNow invoices to steal ~$50,000 ACH payments.

Microsoft detected over one million messages in a BEC campaign running August 3-5, using AI-assisted phishing templates, executive impersonation, and fabricated ServiceNow subscription invoices to trick finance teams into authorizing fraudulent ACH payments of roughly $50,000. The US received 87.7% of volume. Attackers used lookalike domains like service-nowinc[.]com registered just days before delivery, with no compromise of ServiceNow itself. Telltale signs included verbose HTML comments, uniform formatting, and inconsistent forwarded-message headers.

GBHackersupdated · 5d agofirst · 6d agoPhishing & fraud in the wild 2 sources

Vishing campaign abuses Microsoft Teams to give attackers a foothold in company networks

Unit 42 details 'Spring Ring', a vishing campaign using fake IT support on Microsoft Teams to reach 150+ employees at 10+ companies.

Palo Alto Networks Unit 42 documented 'Spring Ring', a voice-phishing campaign that ran January to April 2026, using 26 attacker identities and fake Microsoft 365 tenants such as 'ITProtectionDepartment' to impersonate internal IT support on Microsoft Teams. One path used Quick Assist or downloaded remote-support tools to run an obfuscated PowerShell script that disabled malware scanning before contacting C2; the other delivered a cloud-hosted file triggering browser hijacking, SMB internal network scanning, and a PetitPotam NTLM relay attempt against domain controllers to gain domain-level privileges. Both intrusion attempts were blocked before attackers reached their objectives. Collaboration-platform phishing alerts rose to 42% of Unit 42's telemetry in early 2026, up from 30%.

Help Net Security · 16d agoPhishing & fraud in the wild1

TWINLOOT Abuses SharePoint and Teams to Steal Credentials and Move Across Networks

Ontinue disclosed TWINLOOT, a Python implant hiding C2 in SharePoint dead drops and Teams TURN relays, harvesting credentials and pivoting via reverse SOCKS5.

Ontinue's Cyber Defense Center identified TWINLOOT during a July 2026 campaign investigation: a modular, PyArmor-hardened Python implant (a 39 MB bootstrap-fat.pyc loader) whose entire C2 infrastructure lives inside trusted Microsoft services. Tasking flows through SharePoint Online file dead drops polled every 15 seconds via the Microsoft Graph API, while interactive operator access uses WebRTC DataChannels relayed by Microsoft Teams TURN servers; Graph traffic is driven by the victim's own headless Edge browser. The implant harvests Windows credentials with fake lock screens, offers a reverse SOCKS5 pivot for lateral movement to SMB, RDP, WinRM, and MSSQL, executes commands, and persists on hosts. Initial access is assessed to be Teams social engineering masquerading as IT support, prompting a PowerShell command to download the payload.

The Hacker News · 29d agoMalware1