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Phishing Attacks Abuse Trusted Email Infrastructure and URL Cloaking to Evade Security Filters

VBSpam Q3 2026 test shows phishers abusing DKIM-aligned domains, Amazon SES, and multi-stage URL cloaking to defeat email filters.

Virus Bulletin's Q3 2026 VBSpam test (AMTSO-LS1-TP207) found phishing campaigns moving payloads past the email itself via browser-fingerprinting gates, redirect chains, and hidden POST requests. Examples include a Dutch McAfee/TotalAV scareware renewal scam, a German overdue-payment Web3 fraud delivered via Amazon SES from DKIM-aligned moolaah.com, and Romanian BCR PSD2 credential phishing embedding IPv6-mapped URLs resolving to 103.193.179.223. Net at Work NoSpamProxy ranked first with a 99.995 score while open-source Rspamd caught only 62.55% of phishing mail.

GBHackers · 1d agoPhishing & fraud in the wild 2 sources

Trezor warns users of email provider breach, phishing attacks

Trezor says attackers breached its third-party email provider and are phishing customers with fake STM32 entropy vulnerability alerts.

Trezor warned customers that threat actors breached its third-party email provider and sent fake 'Critical Security Alert: STM32 Entropy Vulnerability' emails from [email protected], claiming wallet seeds were exposed to brute-force attacks; the phishing domain has been taken down while Trezor investigates. This follows the ShipMonk breach, revised upward from about 14,000 to 81,000 customers (including 67,000 additional US customers) who received orders between May 10 and August 8, 2026. Attackers reportedly exploited a Metabase SQL injection zero-day to access ShipMonk data, and ShinyHunters sent extortion emails.

BleepingComputerupdated · 5d agofirst · 6d agoData breach in the wild 6 sources

Revolut Data Breach Via Fake Government Requests – What We Know So Far

Revolut confirmed attackers extracted customer KYC records by sending fraudulent data requests from a spoofed or compromised government agency email domain.

Revolut confirmed a data breach in which an unauthorized party obtained sensitive customer records by submitting fraudulent information requests from an email account on a legitimate government agency domain with valid SPF/DKIM/DMARC authentication. Disclosed data could include full names, dates of birth, passport or driving-license copies, onboarding facial images, IBANs, account statements, withdrawal records, and complete transaction histories including Bitcoin activity. Crypto investigator ZachXBT assessed the operation targeted high-net-worth users, while a threat actor using the name 'IAmNotAVillain' claimed Italian law-enforcement departments were compromised over six months with 147 GB of material, claims that remain unverified. Revolut says only a limited number of customers were affected, blocked the email address, and notified regulators and affected customers, stating its systems and funds were not compromised.

Cyber Security News · 1d agoData breach

Fake Voicemail SVG Attachments Fuel Large-Scale Phishing Campaign

Large-scale phishing campaign used fake voicemail SVG attachments to evade email defenses, targeting 5,527 organizations with 26,000+ messages.

A large-scale phishing campaign distributed fake voicemail notifications as SVG attachments, a format that helps bypass many email security controls. The campaign targeted 5,527 organizations with more than 26,000 malicious messages, apparently aiming to lure recipients into credential-harvesting actions.

Infosecurity Magazine · 19d agoPhishing & fraud

Threat Actor Generates 1M Personalized Fraud Emails in 3 Days

Cybercriminals used AI to generate 1 million personalized fraud emails in three days, eliminating the traditional volume-versus-credibility tradeoff.

Dark Reading reports that a threat actor used AI to generate approximately 1 million personalized fraudulent emails within three days. The article highlights that AI now lets malicious email campaigns combine high volume with high credibility, removing a historic constraint on phishing operations. No specific gang, victim list, or tooling is named in the available text.

Dark Reading · 5d agoPhishing & fraud in the wild

Attackers conceal phishing lures using invisible Unicode characters

Threat actors use invisible Unicode characters (ASCII smuggling) to hide phishing lures and evade email security filters.

Threat actors have adopted the ASCII smuggling technique in phishing campaigns, embedding invisible Unicode characters in emails to conceal malicious lures. The approach is designed to evade email security filters that scan for visible phishing indicators. The report gives no victim counts or named campaigns.

BleepingComputer · 10d agoPhishing & fraud in the wild

Once popular for attacking AI, ASCII smuggling is embraced by spammers

Spammers adopt ASCII smuggling—invisible Unicode tag characters—to evade email filters, with Microsoft Defender detections spiking to 2.5 million per day.

ASCII smuggling hides text in Unicode tag characters (e.g., U+E0041 for "A") that are invisible to humans but readable by LLMs and text processors. The technique gained attention as a stealthy prompt-injection vector and is now used by spammers to obfuscate keywords from email detectors. Microsoft reported Defender for Office smuggling detections jumped from roughly 21,000 per day to over 1.3 million in early February, reaching 2.5 million within four days, before falling sharply in mid-May.

Ars Technica · Security · 12d agoPhishing & fraud

What’s the Scam?

Bruce Schneier reports AI-generated fake thank-you replies to his newsletter confirmations from throwaway Gmail accounts; the scam's goal is unclear.

Bruce Schneier describes receiving a burst of AI-generated, one-line praise emails replying to Crypto-Gram newsletter confirmation messages, sent from random-character Gmail addresses. None of the senders actually subscribed, and they did not respond when he replied, weakening a pig-butchering theory. The campaign appears automated, but its objective has not been identified.

Schneier on Security · 15d agoPhishing & fraud

Hidden Prompts Trick AI Into False Email Summaries

Attackers can hide prompts in invisible HTML within emails to manipulate AI email summarizers into producing misleading summaries.

Dark Reading reports that simple HTML invisible to users can manipulate AI-powered email summarizers into generating false or malicious summaries. The technique is a form of prompt injection delivered through hidden email content. It creates risk that decision-makers act on manipulated AI-generated email summaries rather than the actual message content.

Dark Reading · 22d agoAI safety & security

ChatGPT Flaw Could Let Attackers Steal Gmail Data Across User Accounts

Check Point found a patched ChatGPT flaw where prompt injection and a shared Artifactory service let attackers covertly exfiltrate Gmail data across accounts.

Check Point Research discovered that ChatGPT's isolated code-execution containers could access a shared internal JFrog Artifactory service, whose item metadata API enabled a bidirectional cross-tenant covert channel between accounts. Attackers could embed hidden prompt-injection instructions in shared conversations or custom GPT configurations, causing a victim's session to silently relay connected Gmail data to another ChatGPT account. In a proof of concept, email data was exfiltrated with the only visible hint being a 'Talked to Gmail' activity label. OpenAI decommissioned the internal Artifactory instance involved, eliminating the channel by publication time.

GBHackers · 7d agoAI safety & security

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

Detect and disrupt AI-themed attacks with Microsoft Defender

Microsoft Threat Intelligence reports criminal campaigns impersonating ChatGPT, Copilot, Claude, and DeepSeek in phishing, AiTM, and malvertising attacks reaching 100,000 emails daily.

Microsoft Threat Intelligence observed a growing set of campaigns that abuse trust in popular AI brands: a ChatGPT-themed phishing campaign sent up to 100,000 emails in one day to steal payment card data, and a Claude-themed campaign used adversary-in-the-middle techniques to harvest credentials and access tokens. Other campaigns included malvertising for a fake AI Windows plugin delivering the Vidar stealer and fraudulent DeepSeek installers distributed via GitHub. Initial access broker Storm-3075 used AI-themed malvertising to distribute payloads for multiple downstream actors, and Microsoft notes the AI services themselves were not compromised. Microsoft also details Defender protections such as Safe Links, Safe Attachments, and attack disruption against these multi-stage lures.

Microsoft Security Blog · 6d agoPhishing & fraud in the wild1

Phishing Campaign Sends Millions of Emails Using Invisible Unicode to Evade Filters

Microsoft warns of a high-volume phishing campaign using invisible Unicode characters to split keywords like 'funding' and evade filters, peaking at 2.37 million daily messages.

Microsoft's Security Research team documented a high-volume phishing operation inserting deprecated Unicode Tags characters (U+E0000-U+E007F) inside financial keywords such as 'funding' so literal-string and regex email filters stop matching them. The campaign ran on a weekly cadence with 1-2.37 million weekday messages between February and May 15, 2026, peaking on February 26, 2026. It used hundreds of disposable finance-themed sender domains and relayed mail through ActiveCampaign's click-tracking infrastructure (acemlnd[.]com, activehosted[.]com), lending legitimate platform reputation. Microsoft ties the activity to an AI-assisted SBA loan phishing campaign that Fortra's FIRE team disclosed in September 2025.

The Hacker News · 12d agoPhishing & fraud in the wild

Nebulon Enterprise Simulated Threats for Phishing Research (NEST-Phish): A Synthetic Enterprise Phishing Email Dataset for Behavioral and Machine-Learning Research

Researchers release NEST-Phish, a synthetic enterprise phishing email dataset with matched legitimate and phishing emails and cue annotations for detection research.

Academic researchers introduce NEST-Phish, a publicly released synthetic enterprise phishing email dataset built around a fictitious organization named Nebulon. It contains matched synthetic legitimate and phishing emails across a broad set of workplace communication themes, each with interpretable phishing-cue annotations. Human-subject categorizations and supervised classifier evaluations indicate the dataset supports meaningful variation in phishing judgments and provides learnable signal for detection models. It is intended to support work on phishing detection, human susceptibility, explainability, and benchmark development.

arXiv cs.CR · 13d agoResearch

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

Hackers Impersonate CEOs in 1 Million Emails to Trick Employees Into $50,000 Payments

A BEC campaign sent over one million fake CEO invoice emails, mostly to US firms, urging ~$50,000 ACH transfers to attacker accounts.

Microsoft analysts tracked a business email compromise campaign that sent more than one million messages between August 3 and 5, with 87.7% targeting US recipients. Emails impersonated CEOs, CFOs, and presidents and carried fake ServiceNow-branded subscription invoices directing accounts-payable staff to make ACH transfers of nearly $50,000 to attacker-controlled accounts. No malicious attachments or malware were used, and researchers observed signs consistent with AI-assisted template development. Lookalike domains such as service-nowinc[.]com and third-party delivery accounts were used, while named firms like ServiceNow showed no evidence of compromise.

Cyber Security News · 5d agoPhishing & fraud 2 sources1

Attackers Use Passkey Phishing to Hijack Microsoft Cloud Accounts and Exfiltrate Data

Microsoft details two campaigns: million-email CEO impersonation ACH fraud and passkey-themed vishing that hijacks Microsoft cloud accounts for data theft and extortion.

Microsoft disclosed a campaign that sent over one million CEO-impersonation scam emails between August 3-5, 2026, targeting U.S. accounts payable departments with fake ServiceNow subscription invoices to induce ACH transfers, using generative AI to tailor templates. A second campaign detected since May 2026 uses passkey/MFA-themed voice phishing posing as the IT help desk, redirecting victims via SMS to counterfeit Microsoft sign-in pages and adversary-in-the-middle or device-code flows to hijack accounts. Post-compromise activity includes adding attacker-controlled authentication methods, high-volume Microsoft Graph activity, SharePoint and OneDrive downloads, and mailbox collection via REST APIs. Microsoft attributes initial access to Storm-3121 (linked to ShinyHunters and Falcon extortion) and Storm-3032 (UNC6671, a BlackFile splinter operating the Helix extortion brand).

The Hacker News · 3d agoPhishing & fraud in the wild2

ChatGPT Sandbox Flaw Lets Attackers Steal Gmail Data Across Accounts via Hidden Channel

Check Point found a cross-account covert channel in ChatGPT sandboxes via shared JFrog Artifactory metadata, enabling session hijacking and Gmail data theft. Now fixed.

Check Point discovered that ChatGPT code-execution containers across different accounts could all reach the same internal JFrog Artifactory instance, whose Item Properties API was readable and writable by all accounts, creating a covert cross-account communication channel. Attackers could plant hidden instructions via pasted prompts, shared chat links, or custom GPTs, then trigger tasks in a victim's session to exfiltrate connected-app data such as Gmail, using ChatGPT's default 'Important actions' setting that permits reads without confirmation. OpenAI confirmed and decommissioned the shared Artifactory instance, closing the channel before publication.

Cyber Security News · 8d agoAI safety & security1

ChatGPT flaw lets attackers pull Gmail data across accounts via a hidden channel

Check Point found a ChatGPT flaw letting attackers read victims' Gmail and connected-app data via hidden cross-session instructions; OpenAI patched it.

Check Point Research discovered a covert cross-account command channel in ChatGPT's code execution environment, where containers meant to be isolated shared metadata through an internal service based on JFrog Artifactory. In a proof of concept, a victim's session was tricked into retrieving Gmail email data and relaying it to an attacker-controlled session during an ordinary-looking interaction, with reach extending to any connected apps the session was authorized for, including Google Drive, Microsoft Teams, and GitHub. OpenAI fixed the issue and decommissioned the internal service; the same shared infrastructure was also involved in the separately disclosed Hugging Face compromise, though via different techniques.

CSO Online · 7d agoAI safety & security

Cisco Secure Email Gateway SQL Injection Vulnerability

Unauthenticated SQL injection in Cisco Secure Email Gateway email parsing enables root command execution via crafted messages; patches released.

A vulnerability in email parsing of Cisco AsyncOS for Cisco Secure Email Gateway allows an unauthenticated, remote attacker to execute arbitrary commands with root privileges on the underlying operating system. Insufficient validation in the email parsing logic lets a crafted email containing malicious SQL statements achieve arbitrary SQL execution and root command execution. Cisco has released software updates, and the companion September 2026 hardening advisory states this flaw is actively exploited.

Cisco Security Advisories · 2d agoVulnerability in the wild

When the Attacker Wears Your Logo: Detecting and Taking Down Impersonation at AI Speed

Cyble details how attackers use lookalike domains and cloned sites for brand impersonation scams and how AI-speed detection enables rapid takedowns.

Cyble describes the growing risk of digital impersonation, where attackers register lookalike domains, clone websites, create fake executive profiles, publish fraudulent job ads, and imitate customer-support accounts without ever breaching the legitimate organization. The goal is to borrow a trusted brand's credibility to make scams look legitimate, with particular risk for professional services, financial, legal, and consulting firms. The piece outlines AI-assisted approaches for detecting and taking down impersonation infrastructure quickly.

Cyble · 28d agoPhishing & fraud

Cisco Secure Email Secure/Multipurpose Internet Mail Extensions Ciphertext Decryption Vulnerabilities

Cisco released an advisory for S/MIME ciphertext decryption flaws in Secure Email that could let unauthenticated remote attackers recover plaintext via machine-in-the-middle.

Multiple vulnerabilities in the S/MIME decryption functionality of Cisco Secure Email stem from insufficient validation of message integrity. An unauthenticated remote attacker could intercept and modify traffic between email gateways using a machine-in-the-middle technique to obtain plaintext from encrypted messages. No workarounds are available; no CVE identifiers or exploitation status were included in the advisory text.

Cisco Security Advisories · 8d agoAdvisory

Revolut handed customer data to fraudsters using government email account

Revolut handed sensitive KYC data of high-net-worth crypto customers to fraudsters submitting fake emergency data requests from a compromised government email domain.

Revolut confirmed it disclosed sensitive customer data—including passport and driver's license copies, verification selfies, bank statements, IBANs, and Bitcoin transaction histories—to attackers who submitted fraudulent emergency data requests from a legitimate government agency email account, apparently an Italian domain. Targets were high-net-worth individuals involved in crypto, including Marc Karpelès and entrepreneur Marc Zeller. A Telegram account claiming responsibility posted stolen data as proof and demanded an extortion payment; the account has since been suspended. Revolut says only a limited number of customers were affected and has alerted the relevant government agency, law enforcement, and regulators. The technique mirrors 2021-2022 Lapsus$-linked fraudulent emergency data request scams against Apple, Meta, and Discord.

The Record · 2d agoData breach

Revolut discloses data breach exposing financial info, passports

Revolut disclosed a breach after a threat actor spoofing a government agency's email domain obtained customer passports, selfies, IBANs, and full transaction histories.

Revolut told affected customers that a threat actor sent a data request from an unauthorized email account on an official government agency's domain, carrying valid domain authentication credentials, and staff fulfilled it believing it legitimate. Exposed data includes identity details, contact information, passport and driver's license copies, KYC facial verification selfies, IBANs, withdrawal records, and full transaction histories including Bitcoin. Revolut calls the number of affected customers 'very limited' but refuses to give exact figures, while ZachXBT says high-net-worth users appear targeted. This follows a 2022 Revolut breach affecting 50,150 customers.

BleepingComputer · 2d agoData breach1· 1 read

Microsoft sees some new wrinkles in invoice-scam emails

Microsoft researchers observed a BEC invoice scam sending 1M+ AI-assisted emails impersonating executives and ServiceNow to request ~$50,000 payments.

Microsoft researchers tracked a campaign of more than one million invoice-scam emails launched in early August, with about 88% of targets in the United States. Attackers impersonated top executives and ServiceNow, fabricating forwarded email threads and invoices to convince accounts payable teams to send payments of nearly $50,000. Microsoft found indicators such as extensive HTML comments and highly uniform template construction consistent with AI-assisted campaign development, though it could not independently establish how much content AI generated.

The Record · 5d agoPhishing & fraud

Russian Hackers Phish EU Officials Over Messaging Apps

Russian nation-state hackers are phishing EU officials via Signal and WhatsApp as espionage shifts from email to messaging apps.

Russian state-linked threat groups have shifted phishing operations away from email toward messaging apps such as Signal and WhatsApp, targeting EU officials. In response, EU governments are trying to move away from popular messaging platforms. The report highlights evolving social engineering tactics in nation-state espionage campaigns against government targets.

Dark Reading · 20d agoThreat actor

Hackers Favor US Eastern Business Hours in M365 Phishing Campaign

KnowBe4 tracked 29,785 phishing emails abusing Microsoft 365 Direct Send to spoof internal senders while timing sends to US Eastern business hours.

KnowBe4 Threat Lab observed 29,785 confirmed phishing emails between July and August 2026 abusing Microsoft 365's Direct Send feature, which lets devices and legacy apps send mail without a dedicated account. The emails appeared to come from trusted internal addresses such as HR or accounting, bypassing email gateways by connecting directly to Exchange Online MX endpoints, with activity peaking on Monday-Tuesday during US Eastern business hours and near-zero weekend volume. About 35% of the messages carried malicious attachments like fake invoices, voicemail alerts, and OneDrive shares, and 4,023 used reply-to addresses on different domains to capture employee responses. Researchers recommended strict DMARC enforcement, connector restrictions, DKIM signing, and checking for the 'X-MS-Exchange-Organization-AuthAs: Anonymous' Exchange header.

Infosecurity Magazineupdated · 12h agofirst · 5d agoPhishing & fraud in the wild 9 sources1

Identity Abuse Through Trusted Communication Channels

Unit 42 explains how attackers abuse trusted enterprise communication and collaboration channels for identity phishing and credential theft, and outlines defenses.

Palo Alto Unit 42 details how attackers exploit enterprise collaboration and communication tools as trusted channels for identity phishing and credential theft. The writeup describes abuse of presumed-trusted messaging paths and outlines defense strategies. It is guidance rather than a report of a specific incident.

Palo Alto Unit 42 · 27d agoPhishing & fraud

Hackers Exploit Critical Cisco Secure Email Gateway Vulnerability in the Wild to Run Malicious Code

Cisco warns attackers actively exploit zero-day CVE-2026-76461 in Secure Email Gateway, gaining unauthenticated root command execution via crafted emails.

Cisco PSIRT confirmed active in-the-wild exploitation of CVE-2026-76461 throughout September 2026, a zero-day in Secure Email Gateway AsyncOS that lets remote, unauthenticated attackers execute arbitrary commands with root privileges by sending maliciously crafted emails containing injected SQL statements. Physical appliances, virtual deployments, and Cisco Secure Email Cloud instances were affected; Cisco deployed server-side remediations for cloud tenants but on-premises admins must patch themselves. Fixes ship in AsyncOS 16.5.0-780 plus branches 16.0.4-3021 and 15.5.5-0141, and no workarounds exist.

Cyber Security Newsupdated · 13h agofirst · 1d agoExploit / PoC in the wild 17 sourcesCVE-2026-76461