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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

Threat Gang 'Springs' Vishing Attacks on Microsoft Teams Users

The 'Spring Ring' operation uses vishing attacks against Microsoft Teams users to hijack sessions, deploy malware, and take over infrastructure.

Dark Reading reports on the Spring Ring threat gang conducting voice-phishing (vishing) attacks against users of Microsoft Teams. The operation aims to compromise collaboration-suite accounts to gain remote access to victim sessions, distribute malware, and potentially seize control of infrastructure. Further technical details were not provided in the available text.

Dark Reading · 14d agoPhishing & fraud1

Microsoft Teams Has Become a Haven for Scammers in China

Scammers in China are exploiting Microsoft Teams and Webex to trick Chinese victims into transferring large sums of money.

WIRED reports that fraudsters are abusing enterprise chat platforms including Microsoft Teams and Cisco Webex to run scams against victims in China. Victims are socially engineered into transferring large sums of money. The campaign has generated a wave of complaints, highlighting how scam groups abuse legitimate business communication tools.

WIRED · Security · 19d agoPhishing & fraud in the wild

New Phishing Attack Creates Malicious Pages Inside the Victim’s Browser

Barracuda details a phishing campaign that renders pages in-browser via blob URLs, routed through Microsoft Teams and cdn.bloom[.]io to evade detection.

Barracuda researchers analyzed a phishing campaign that generates a blob URL to render the phishing page entirely inside the victim's browser, leaving no static page for scanners to inspect. The chain begins with a Docusign-themed email containing a calendar invite, followed by a crafted redirect through Microsoft Teams to a resource on cdn.bloom[.]io that the browser converts into the blob URL. Service workers, iframes, and a hidden command-and-control configuration indicate the page is part of a centrally managed phishing platform that can be updated and steered across victims. Researchers recommend inspecting blob URL activity, monitoring OAuth authorization flows, and analyzing the full click path in email security controls.

SecurityWeek · 8d agoPhishing & fraud in the wild

Cybercriminals are building phishing pages that exist only inside victims’ browsers

Barracuda details a DocuSign-themed phishing campaign that renders login pages locally via blob URLs, abusing genuine Microsoft OAuth and Teams infrastructure.

Barracuda researchers describe a phishing campaign that starts with DocuSign-themed emails carrying calendar invites pointing to genuine Microsoft OAuth endpoints, then routes victims through Microsoft Teams to a resource hosted on cdn.bloom[.]io. The login page is assembled entirely inside the victim's browser from a blob URL, registers a service worker, and runs inside a sandboxed iframe that receives live instructions from the attacker's backend. Hidden command-and-control configuration indicates the page is part of a centrally managed phishing platform that can be updated and steered across many victims. Barracuda recommends phishing-resistant MFA such as FIDO2 keys or passkeys, monitoring of OAuth flows and redirect chains, and behavior-based identity controls rather than URL blocklisting.

Help Net Security · 7d agoPhishing & fraud in the wild

New Phishing Attack Uses Blob URLs to Hide Malicious Pages From Security Scanners

Barracuda detailed a DocuSign-themed phishing campaign that renders credential-harvesting pages as browser blob URLs, evading URL reputation and blocklist defenses.

Barracuda researchers report a credential-harvesting phishing campaign that starts with a DocuSign-themed email containing a calendar invitation and routes victims through legitimate Microsoft OAuth endpoints and Microsoft Teams. A crafted redirect parameter leads Teams to load external content from cdn.bloom[.]io, which the browser renders as a blob URL — a session-only address held in local memory with no persistent public URL to crawl, categorize, or blocklist. The locally generated page registers a service worker, runs inside a sandboxed iframe, and is dynamically steered by backend infrastructure, indicating a centrally managed phishing platform. Barracuda recommends phishing-resistant MFA such as FIDO2 keys and passkeys, monitoring OAuth flows and redirect chains, and Teams malicious URL protection.

GBHackers · 7d agoPhishing & fraud in the wild

New N0va Phishkit Targets North America and EU: A Growing Identity Risk for SOCs

ANY.RUN researchers uncovered the N0va phishkit targeting government, technology, consulting, and healthcare organizations across North America and the EU via device code phishing.

The N0va phishkit uses lures imitating Microsoft Teams, SharePoint, OneDrive, DocuSign, Google Drive, Dropbox, Zoom, and Adobe Sign to draw victims into a device code authentication flow. After the user completes legitimate authentication, N0va captures access and refresh tokens and abuses token-exchange and device-registration mechanisms to establish persistent SSO access to corporate resources. Because the flow relies on real Microsoft authentication, it can evade MFA-focused detections, and token access can outlive takedown of the phishing page. ANY.RUN says it observed the campaign in sandbox sessions, with targeting spanning government, technology, consulting, and healthcare sectors.

Cyber Security News · 7d agoPhishing & fraud in the wild1

N0va Phishkit Targets US and EU Businesses: A New Challenge for Identity Security

N0va phishkit targets US and EU organizations with trusted-brand lures, capturing tokens via legitimate authentication flows to gain SSO access to corporate resources.

The N0va phishing kit targets organizations in government, technology, consulting, and healthcare across North America and Europe with lures impersonating Microsoft Teams, SharePoint, OneDrive, DocuSign, Google Drive, Dropbox, Zoom, and Adobe Sign. Victims are guided through legitimate authentication flows, including device code phishing, after which N0va captures access and refresh tokens and abuses token-exchange or device-registration mechanisms to establish SSO access. ANY.RUN tracks the campaign via a characteristic /api/verification/init URL pattern and demonstrates detection in its interactive sandbox.

The Hacker News · 1d agoPhishing & fraud in the wild 2 sources2

Risky Bulletin: Ukraine's top prosecutor resigns amid scam call center scandal

Ukraine's top prosecutor Ruslan Kravchenko resigned after NABU arrested a deputy for taking bribes protecting scam call centers running fake investment platforms.

Ukraine's anti-corruption bureau NABU arrested Serhiy Kropyva, Deputy Head of International Cooperation at the Prosecutor General's Office, alleging officials took monthly protection fees from a network of 100-500 scam call centers luring victims into fake investment platforms, with bribes reportedly growing from $700,000 to $3.5 million per month. Prosecutor General Ruslan Kravchenko resigned on Monday, calling it a political decision, while Kropyva was fired with bail set at 120 million hryvnias ($2.7 million) and over 100 call centers shut down in the past month. The newsletter also briefly covers a cyberattack crippling more than 80 Luxembourg medical practices via payment vendor BMS Engineering, ShinyHunters' claimed theft of 200,000 Florida DMV driver records, a cyberattack on the American Meteor Society, and school closures in Springfield, Massachusetts.

Risky Business News · 8d agoPhishing & fraud

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

Inside Knight Office, a New M365 AiTM Phishing Kit

Huntress details Knight Office, a new AiTM phishing kit stealing Microsoft 365 session tokens and registering attacker-controlled devices.

Huntress investigated an August 18, 2026 adversary-in-the-middle attack using the Knight Office phishing kit, which captured Microsoft 365 session tokens via a DocuSign-style lure routed through a Monday.com tracking link and a compromised Joomla site. After token capture, the actor enrolled an unauthorized host in Microsoft Entra ID and bound a Windows Hello for Business key credential to the account. The kit's operator console, found at IP 104.37.188.94, is built on Python Flask and hosts at least 25 .vu phishing domains. Telemetry links the kit to at least nine token-replay logins in two weeks and roughly 700 reported lure emails since April.

Huntress · 15d agoPhishing & fraud in the wild1

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