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Hackers Pose as IT Support to Hijack Microsoft 365 Accounts With Fake Passkey Alerts

Microsoft warns of vishing campaigns by Storm-3121 and Storm-3032 hijacking Microsoft 365 accounts via fake passkey alerts, adding attacker-controlled MFA and exfiltrating cloud data.

Microsoft Security Research has tracked the campaign since May 2026: callers posing as IT helpdesk staff tell employees to urgently update passkeys, MFA, or SSO settings via domains such as add-passkey[.]com and contoso[.]add-passkey[.]com. The lures lead to adversary-in-the-middle phishing or device-code authentication flows that yield credentials, session tokens, or OAuth tokens, after which attackers enroll their own MFA methods for persistence and run Microsoft Graph reconnaissance. They then collect SharePoint, OneDrive, and sometimes Exchange Online data at deliberately low rates (often under 1,000 files or messages per hour), with python-httpx seen in high-volume file access. Microsoft attributes initial access tradecraft to Storm-3121 and Storm-3032, linked respectively to ShinyHunters/Falcon and BlackFile/Helix extortion operations.

GBHackersupdated · 11h agofirst · 6d agoPhishing & fraud in the wild 9 sources1

Hackers Can Turn AI Workflows Into Privileged Data-Stealing Proxies Without Jailbreaking Models

Noma Labs describes Workflow Identity Hijacking, where unauthenticated external requesters abuse AI workflows' privileged service accounts to exfiltrate internal data without prompt injection.

Noma Labs identified 'Workflow Identity Hijacking,' an authorization gap in enterprise AI workflows triggered via public inboxes, web forms, GitHub issues, and support systems. Attackers submit legitimate-looking requests that cause workflows to retrieve and disclose internal data using privileged service accounts or creator credentials, without any prompt injection or model misbehavior. Defenses include propagating requester identity through workflows, short-lived scoped tokens, and access-control checks before sensitive actions.

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

Identity-Based AI Attack Threatens Security of Enterprise Data

Dark Reading describes 'workflow identity hijacking,' an identity-based attack that hijacks enterprise AI workflows through unauthenticated entry points.

Dark Reading reports on 'workflow identity hijacking,' an identity-based attack technique targeting AI-driven enterprise workflows. The technique reportedly bypasses standard security controls by sending a basic request through an unauthenticated entry point to hijack an organization's data. The teaser provides no further technical detail, affected products, or attribution.

Dark Reading · 7d agoAI safety & security

Mirage2FA Hijacks Companies’ Microsoft 365 Sessions, with Over 4K Victims in the US

Mirage2FA phishing-as-a-service kit uses AiTM attacks to hijack Microsoft 365 sessions, with over 4,000 US victims.

ANY.RUN analyzed Mirage2FA, an active phishing-as-a-service toolkit that steals Microsoft 365 credentials and authenticated sessions through Adversary-in-the-Middle phishing pages. About 63.7% of identified victims are in the US, with Technology, Manufacturing, and Education the most targeted industries. Thousands of compromise events were recorded between 2024 and 2026.

ANY.RUN · 29d agoPhishing & fraud in the wild1

What Is Account Takeover Fraud? A Comprehensive Guide | Huntress

Huntress published an educational guide explaining account takeover (ATO) fraud, how attackers steal credentials, and steps to detect and prevent it.

Huntress released a comprehensive guide on account takeover fraud, which occurs when attackers steal login credentials to gain access to victim accounts. The article is educational rather than incident reporting, covering detection signals and prevention measures such as credential protection. No specific breach, actor, or vulnerability is described.

Huntress · 26d agoPhishing & fraud

Infostealers are hijacking Claude accounts at users’ expense

Malwarebytes reports infostealers are stealing Claude session cookies to hijack Anthropic accounts and consume victims' usage at their expense.

Anthropic warned that infostealer malware operators are harvesting Claude session cookies from infected machines. Attackers replay the stolen cookies to take over users' accounts and consume their usage quotas, affecting the victims' own access. The activity involves observed account hijacking rather than a flaw in Claude itself.

Malwarebytes Labs · 15d agoMalware in the wild

MFA's Weakest Link: Account Recovery Is the New Attack Path

Help desk account recovery is increasingly the weakest link in MFA-protected identities, as Scattered Spider's impersonation-driven Marks & Spencer attack demonstrated.

As MFA, conditional access, and phishing-resistant factors raise the cost of direct account takeover, attackers increasingly target the recovery process, convincing service desk staff to reset passwords or re-register MFA on attacker-controlled devices. CISA, FBI, and partner advisories describe Scattered Spider posing as employees to trigger such resets; the 2025 Marks & Spencer attack began this way and led to ransomware with an estimated £300 million profit impact. Microsoft now describes Entra ID account recovery as a high-assurance process, and the article promotes Specops Secure Service Desk for verified identity workflows.

BleepingComputer · 7d agoPhishing & fraud

WeChat Worm Can Hijack Accounts Without Victims Answering Calls

Researchers demoed WeWorm, a zero-click WeChat worm hijacking accounts via incoming VoIP calls using a memory corruption flaw; Tencent patched it in August.

Researchers at Calif exploited a memory corruption bug in WeChat's VoIP system, taking over accounts through an incoming call even if the victim never answers or touches the phone. The attacker must already be a WeChat contact, but compromising a friend's account bypasses this, and chained calls spread the worm across three Android and iOS test phones in seconds. Tencent fixed the flaw in Android 8.0.77 and iOS 8.0.76 released in August, and researchers found no evidence of real-world exploitation. WeChat and Weixin reported 1.418 billion combined monthly active users at the end of 2025.

Security Affairs · 8d agoExploit / PoC

Attacker Hijacks AI Coding Assistant Session, Spreads Shai-Hulud Across About 100 Repositories

Mandiant says an attacker hijacked an AI coding-assistant session at a SaaS provider and spread the Shai-Hulud worm across roughly 100 repositories, stealing secrets.

Mandiant's September 2026 report describes an attacker hijacking an active AI coding-assistant session at an unnamed SaaS provider, then getting a poisoned package recommendation accepted and installing an infostealer via a malicious PyPI package. The attacker stole GitHub OAuth tokens, deployed the self-spreading Shai-Hulud worm across approximately 100 internal repositories, and stole repository secrets and product source code. Poisoning a package in the company's official namespace caused a second employee to pull the compromised version and become infected. Mandiant recommends verifying AI-recommended dependencies against checksums and allowlists, keeping secrets out of extension reach, and routing dependency traffic through internal repositories.

The Hacker News · 12h agoData breach in the wild

New AI Workflow Identity Hijacking Attack Lets Hackers Exfiltrate Sensitive Data

Noma Labs disclosed Workflow Identity Hijacking, an AI automation flaw letting anonymous users trigger privileged data exfiltration without prompt injection or stolen credentials.

Noma Labs researcher Sasi Levi described Workflow Identity Hijacking, where AI workflows process untrusted input from low-privileged or anonymous users but execute downstream actions with the workflow creator's elevated permissions, turning the pipeline into an unauthenticated proxy. Unlike prompt injection, the model is not tricked; the flaw is a missing authorization check between the requester and the privileged actions. Noma Labs also disclosed and helped fix a similar issue in Google Workflows, and linked the problem to the earlier GitLost research on GitHub Agentic Workflows. Recommended mitigations include per-user identity propagation, least-privilege service accounts and authorization checks before every downstream action.

GBHackers · 6d agoAI safety & security

Hackers Abuse YouTube Gaming Channels and SEO Poisoning to Deploy RATs and Chrome Hijacker

Unit 42 exposed CL-CRI-1171, a pay-per-install operation using YouTube gaming channels and SEO poisoning to deliver RATs and a Chrome hijacker.

Palo Alto Networks Unit 42 identified over 10,000 OfferLoader samples and 11 YouTube channels pushing trojanized installers via gaming lures and SEO-poisoned searches for tools like WinDirStat and Bluetooth drivers. Trojanized Inno Setup installers spawn three payload branches: Insomnia RAT (dual Node.js/Python backdoor that disables Microsoft Defender), ARKTunnel (undocumented RAT hiding its payload in a bitmap image and tunneling TCP/UDP), and Docro Hijacker (alters Chrome protected preferences to hijack search and affiliate links). The pay-per-install model sells each infection to multiple buyers, reaching gamers as well as corporate and government endpoints.

Cyber Security News · 2d agoMalware in the wild1

Anthropic cracks down on hijacked user accounts mining AI tokens

Commodity infostealer malware hijacked Anthropic user accounts, letting criminals mine AI tokens on victims' paid usage; Anthropic cracked down on affected accounts.

The Register reports that Anthropic is cracking down on user accounts hijacked through commodity malware that steals authenticated browser sessions. With the stolen sessions, thieves ran AI workloads to mine tokens, freeloading on victims' paid usage allowances. The campaign illustrates how infostealer operators now monetize AI platform credentials and sessions, not just financial accounts.

The Register · Security · 16d agoMalware in the wild

Credential Theft: How Attackers Steal & Use Stolen Credentials

Huntress explains how attackers steal credentials through phishing, AitM, infostealers, and dumping, then use them for lateral movement, BEC, and ransomware.

Huntress published an educational overview of credential theft, citing that roughly 70% of confirmed data breaches begin with stolen credentials. It details acquisition methods including phishing, adversary-in-the-middle attacks that capture MFA session tokens, infostealers (nearly a quarter of threats Huntress observed in 2025), Mimikatz-based credential dumping, credential stuffing, and password spraying. The piece then covers post-theft actions such as lateral movement, privilege escalation, account takeover, business email compromise, and ransomware, and closes with behavioral detection guidance and layered prevention strategies.

Huntress · 6d agoResearch

Major Cyber Attacks in August 2026: US and EU Businesses Hit by Session Hijacking, Remote Access, and Insider Risk

ANY.RUN's August 2026 roundup shows US and EU firms hit via Microsoft 365 session hijacking, remote-tool abuse, and hiring lures.

ANY.RUN's August 2026 review catalogs attacks on US and European businesses abusing Microsoft 365 sessions, legitimate remote-management tools, and business-themed files. Observed techniques included account takeover, session hijacking, persistence via remote access, credential exposure, and exploitation of hiring processes. The report stresses that attacker activity frequently resembled legitimate business behavior.

ANY.RUN · 15d agoThreat actor in the wild1

AI Customer Service Bots Can Be Tricked Into Stealing Security Codes and Acting as Victims

DEF CON 34 research shows AI customer-service agents can be manipulated via prompt injection and email tricks to leak OTPs and act as victims.

Inti De Ceukelaire, presenting at Bug Bounty Village during DEF CON 34, demonstrated attacks against AI-powered customer service bots with access to customer profiles, billing data, support inboxes, and refund tools. Techniques include transcript-based phishing from trusted support addresses, From-header identity confusion, email normalization abuse to bypass OTP rate limits, and knowledge-base poisoning via RAG crawlers. He recommends separating untrusted content from system prompts, session-bound authentication, consistent email normalization, server-side tool validation, and least-privilege permissions for AI agents.

Cyber Security News · 8d agoAI safety & security

From Infostealer Log to Marketplace Listing: A Technical Walkthrough of the Credential Theft Pipeline

Cyble walkthrough maps how infostealer logs move from endpoint infection through aggregation and enrichment to dark web credential marketplace sales.

Cyble breaks the credential theft pipeline into stages: infostealer execution harvesting browser credential stores, cookies, session tokens, crypto wallets, and FTP configurations; aggregation of stealer logs via C2 panels into bundled archives; parsing and enrichment against previously leaked datasets; and final listing on dark web marketplaces. Enrichment adds employer and role context that raises prices and enables credential stuffing across reused passwords. The report advises SOC teams to monitor stealer logs and marketplace chatter early rather than waiting for breach alerts.

Cyble · 6d agoMalware1

The Hidden Instructions That Can Hijack AI Agents

Hidden prompt injections embedded in documents and metadata can hijack autonomous AI agents, causing data exfiltration and out-of-policy actions at machine speed.

Bowbridge warns that hidden indirect prompt injections, embedded in documents, metadata, emails, images, and code repositories, can cause autonomous AI agents to treat attacker-controlled content as trusted guidance. Because agents inherit user privileges, act silently, and lack human judgment, injections can lead to data exfiltration or file poisoning that traditional security controls cannot detect. A real-world example involved a supplier quote whose metadata instructed an agent to override guidance and select the most expensive option. Bowbridge recommends scanning documents before agents process them.

SecurityWeek · 8d agoAI safety & security

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 · 4d agoPhishing & fraud in the wild1

BragJack Attack Can Turn a Browser's Agentic AI Against It

New BragJack attack hijacks browsers' built-in agentic AI to access data, run malicious actions, and exfiltrate information.

Dark Reading describes BragJack, a new attack type that hijacks AI assistants built directly into web browsers. The technique allows attackers to access sensitive information, execute malicious actions through the agent, and exfiltrate data. The brief excerpt does not name affected browsers, CVEs, or confirm exploitation in the wild.

Dark Reading · 9h agoAI safety & security

“Zero-click” WeChat worm could hijack accounts and spread via a single call

Researchers discovered a critical memory corruption flaw in WeChat's VoIP stack enabling a zero-click worm, WeWorm, that hijacks accounts via calls; Tencent patched it.

Calif researchers weaponized a memory corruption issue in WeChat's VoIP stack into "WeWorm", a worm that spreads through WeChat calls without user interaction, hijacks each victim's account, and propagates via saved contacts across iOS and Android, potentially reaching millions of devices within hours. Exploitation takes seconds and grants full account control, and chaining with other reported Android/iOS bugs could lead to full device control. Tencent issued updated WeChat versions for iOS and Android and applied server-side mitigations; technical details remain withheld. WeChat has over a billion users, overwhelmingly in China.

Help Net Security · 8d agoVulnerability

CaptiveCrunch: Midnight Blizzard Weaponizes Hotel Wi-Fi Captive Portals to Steal Microsoft 365 Credentials

Zscaler details CaptiveCrunch: Midnight Blizzard's Storm-2945 compromises hotel Wi-Fi captive portals to redirect guests and harvest Microsoft 365 credentials via device code phishing.

Zscaler ThreatLabz analyzed the CaptiveCrunch credential theft campaign first reported by Microsoft on July 31. Microsoft attributes the activity to Storm-2945, a sub-cluster of Russia-linked Midnight Blizzard (APT29, Cozy Bear, NOBELIUM, BlueBravo). The actor manipulates DNS and HTTP traffic on captive portal networks at hotels and conference centers, redirecting victims to attacker-controlled infrastructure for Microsoft 365 credential harvesting, device code phishing, and malware delivery. Evidence indicates shared captive portal services were compromised rather than each venue being breached individually.

Zscaler ThreatLabz · Aug 11, 2026Threat actor in the wild

The Top 4 Threats We Found by Investigating Every Alert for a Quarter

Prophet Security's quarterly threat report finds identity attacks made up roughly half of confirmed malicious activity, with stolen authenticated sessions bypassing conditional access controls.

Between May 1 and July 31, 2026, Prophet Security investigated every alert in customer environments immediately on arrival; about 7% of completed investigations were confirmed malicious. Direct account/session attacks made up roughly 18% of confirmed activity, with replayed authenticated sessions bypassing conditional access since no re-authentication occurs. Infostealer activity affected about a quarter of investigated organizations, mostly delivered via browsers through compromised websites, malicious ads, sponsored search results and ClickFix fake CAPTCHA gates, with payloads including Lumma Stealer, Vidar, HijackLoader and AsyncRAT. Credential phishing was the largest category at about 28%, with adversary-in-the-middle relays revealed by seconds-long MFA approvals from distant countries and MFA fatigue attacks exploiting automatic unlock policies.

BleepingComputer · 6d agoThreat actor in the wild

X says attackers are targeting user accounts after the launch of X Money

X is investigating a wave of unsolicited password reset emails targeting users after the X Money payments launch, with no confirmed breaches yet.

Numerous X users reported unsolicited password reset emails following the launch of X Money, the platform's new payments service with accounts held at FDIC-insured Cross River Bank. Product engineer Mridul Singhai said the company found no evidence of successful breaches or mass account takeovers, while the Grok chatbot confirmed attackers are mass-triggering resets using public usernames. Users are being advised to enable two-factor authentication and Password Reset Protect while the investigation continues.

TechCrunch · Security · 15d agoPhishing & fraud in the wild

Hackers Expose Data of 1.2 Million Heights Finance Customers

Heights Finance is notifying over 1.2 million customers that hackers accessed a third-party cloud platform holding contact, bank and government ID data.

Heights Finance, a U.S. consumer lender, discovered unauthorized access on May 7, 2026 to a third-party cloud platform used to store customer data; its internal loan management systems and operations were not affected. Exposed data varies by person and may include contact details, financial and bank account information, government IDs and dates of birth for customers, loan applicants, inquirers, and former borrowers of Curo Management and related brands. The company is offering 24 months of free credit monitoring and identity protection; dark web monitoring found no evidence of publication and no threat actor has claimed responsibility.

Security Affairs · 29d agoData breach in the wild