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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

Phishing Attacks Serve Browser-in-the-Browser Pages, Rogue RMM Persistence

Phishing emails with browser-in-the-browser fake Adobe pages trick users into installing rogue ScreenConnect clients granting persistent remote access.

Huntress SOC investigated two August incidents where phishing links led to fake CAPTCHA checks and Adobe PDF Reader lures rendered as browser-in-the-browser (BiTB) pages spoofing legitimate domains like get.adobe.com. Victims downloaded what they believed was Acrobat Reader but actually installed ScreenConnect.ClientSetup.exe from attacker infrastructure, yielding two rogue ScreenConnect clients with service-based persistence. The attacker used cmd.exe and curl to stage a second client connecting to 144.172.115.59, leveraged a ScreenConnect Trial Relay domain for stealth, and ran HideCursor.exe as a defense-evasion binary. Incident 2 arrived via AT&T Office@Hand (RingCentral), with both chains stopped before broader impact.

Huntress · 8d agoPhishing & fraud in the wild

ApateWeb: An Evasive Large-Scale Scareware and PUP Delivery Campaign

Unit 42 uncovers ApateWeb, a campaign using over 130,000 domains and multilayered redirects to deliver scareware, adware and PUPs to millions of users.

Unit 42 discovered ApateWeb, a large-scale campaign using a network of more than 130,000 domains to deliver scareware, potentially unwanted programs, adware including a rogue browser and browser extensions, and scam pages. The campaign uses a three-layer structure with deceptive emails as the entry point, centralized victim tracking via UUIDs, intermediate adware or anti-bot redirections, and evasion tactics such as cloaking, bot detection error pages, and wildcard DNS abuse. Activity spiked since August 2022, with several hundred attacker-controlled sites remaining in Tranco's top 1 million rankings and millions of monthly hits; Unit 42 blocked an estimated 3.5 million sessions across 74,711 devices in November 2023.

Palo Alto Unit 42 · Aug 17, 2026Phishing & fraud in the wild

Five Venezuelan Nationals Plead Guilty in Kansas ATM Jackpotting Attempt

Five Venezuelan nationals pleaded guilty to failed ATM jackpotting attempts in Kansas as the FBI reports 700+ US incidents in 2025.

The five defendants traveled from Indiana to Kansas in December 2025 and tried to install malware on ATMs in Wamego and Manhattan, planning to remotely trigger the machines to dispense cash. Both attempts failed — one triggered an alarm — and the men were arrested days later after surveillance captured the thefts. All five pleaded guilty to conspiracy to commit bank larceny; one has received a nine-month prison sentence. The FBI counted more than 700 jackpotting incidents in 2025 with over $20 million in losses, part of 1,900 incidents since 2020.

Security Affairs · 15d agoPhishing & fraud

PAPERMILL Hackers Abuse Signed Notepad++ to Deploy VenomRAT in Tax Audit Attacks

PAPERMILL phishing campaign abuses a signed Notepad++ copy and tax-audit lures to deploy VenomRAT against targets in India.

JUMPSEC tracks PAPERMILL as an emerging cluster whose emails pass SPF, DKIM, and DMARC and deliver tax-audit themed disk images. The mounted image pairs a legitimately signed, renamed executable with a rogue libcurl.dll for DLL sideloading, then uses a Donut shellcode loader to run VenomRAT 6.0.3 in memory with hidden VNC, data-stealing, and file-grabbing capabilities. The loader includes anti-analysis checks and RunOnce persistence, and lures plus China-connected infrastructure overlap with the Silver Fox ecosystem, though attribution remains unconfirmed.

Cyber Security News · 1d agoPhishing & fraud in the wild 2 sources

New Phishing Campaign Abuses Windows Mshta.exe to Steal Credentials and Secrets

Fortra researchers track an active phishing campaign targeting Spanish speakers that abuses mshta.exe to run HTA payloads for reconnaissance and credential theft.

Fortra's FIRE team says a phishing campaign active since June 2026 targets Spanish-speaking users with invoice ('Facturación') and judicial ('Aviso Judicial') lures, many sent via libero.it/italiaonline.it infrastructure with SCL:-1 markings to bypass anti-spam. Clicking embedded links delivers an HTA launcher executed via mshta.exe, which hides its window off-screen, builds dynamic C2 URLs, and performs reconnaissance using WMI, PowerShell, and environment-variable inspection. A second-stage JavaScript dropper uses HTML smuggling to reconstruct a Base64-encoded ZIP in the browser, delivering a 7-Zip self-extracting executable disguised as a Firefox installer; staged design allows later delivery of credential stealers or ransomware. Defenders are urged to block archivogratuito[.]online and shortener domains goo[.]su, abrir[.]link, and abre[.]ai, and to restrict mshta.exe execution via AppLocker or ASR rules.

GBHackers · 5d agoPhishing & fraud in the wild1

How Threat Actors Are Turning Trusted AI Platforms Into an Attack Surface

Huntress details campaigns abusing Claude Artifacts, claude.ai/share links, and ChatGPT/Grok conversations to deliver SectopRAT, MacSync, and AMOS stealers.

Huntress SOC documented nine months of campaigns in which attackers weaponized trusted AI platform features—Claude Artifacts, public claude.ai/share links, and indexable ChatGPT/Grok conversations—to deliver malware. The July FakeAgent campaign hit more than 29 organizations via a malicious Claude Artifact posing as a Claude Desktop download page that redirected to SectopRAT. A claude.ai/share link disguised as an Apple Support guide tricked a victim into running a curl command that deployed the MacSync stealer, harvesting cookies, credentials, keychain secrets, Telegram sessions, and SSH/cloud keys, while SEO-poisoned ChatGPT and Grok conversations delivered the AMOS stealer via ClickFix-style instructions.

BleepingComputer · 5d 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

ASCII smuggling isn't just an AI security risk

Microsoft tracked a phishing campaign peaking at 2.37 million daily messages that hid financial-lure keywords with invisible Unicode tag characters to evade filters.

Microsoft researchers uncovered a large phishing campaign that inserted invisible Unicode tag characters (e.g., U+E0020) inside common financial keywords like 'funding', splitting words so keyword, signature, and regex matches fail. The campaign peaked at more than 2.37 million messages in late February 2026, ran from about 150 finance-themed sender domains on a strict weekday-only schedule, and gradually declined to under 20% of peak weekday volume by late March, with residual spikes through mid-June. The technique repurposes ASCII smuggling, normally used for indirect prompt injection against AI assistants, for traditional email phishing evasion. Microsoft advises defenders to strip or fold invisible Unicode code points before content matching and to watch for bulk weekday spikes from churning finance-themed domains.

The Register · Security · 12d agoPhishing & fraud in the wild1