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BigBear Microsoft 365 phishing service bypassed MFA at 258 organizations

The BigBear 2.0 phishing-as-a-service framework bypassed MFA to steal 5,000+ Microsoft 365 credentials across 258 organizations, CloudSEK researchers found.

CloudSEK researchers gained administrator access to the BigBear 2.0 control panel, finding the phishing-as-a-service operation ran 42 VPS nodes all configured to target Microsoft 365. The framework has been used to bypass multi-factor authentication at 258 organizations and harvest more than 5,000 credentials, indicating an active credential-theft campaign against enterprise tenants.

DataBreaches.net · 9d agoPhishing & fraud in the wild1

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 · 14d agoPhishing & fraud in the wild1

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 · 19h agofirst · 5d agoPhishing & fraud in the wild 8 sources2

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 · 16d agoThreat actor in the wild1

Confusedpilot Attack Targets Ai

ConfusedPilot attack exploits Microsoft 365 Copilot's retrieval pipeline to expose confidential enterprise data in AI responses.

ConfusedPilot targets Microsoft 365 Copilot's retrieval-augmented generation pipeline, potentially causing the assistant to surface confidential enterprise content in generated responses. Researchers disclosed the technique as a Copilot data confidentiality flaw affecting search and caching behavior. It highlights the emerging attack surface in enterprise AI assistants that access corporate data stores.

Infosecurity Magazine · Aug 16, 2026AI safety & security in the wild

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

Ransom Busters Claims It Hacked Ransomware Servers, Asks Victims for Up to $60,000

GuidePoint reports a ransomware affiliate posing as 'Ransom Busters' charges victims $20,000-$60,000 to delete stolen data, and details UNC6671's $8M AitM extortion wave.

GuidePoint's GRIT team reports that 'Ransom Busters', likely a ransomware affiliate active across multiple RaaS operations including DragonForce, Settra and Anubis, proactively emails victims claiming it deleted their stolen data and backups for a $20,000-$60,000 fee, citing claimed access to RaaS administrative panels for over three years. Two analyzed intrusions shared tooling: SoftPerfect Network Scanner for reconnaissance, s5cmd-based exfiltration to AWS cloud storage, an RMM tool installed via PowerShell, a backdoor account with password 'Numlock!123' and the same attacker hostname DESKTOP-BBETH6K. Separately, GRIT detailed UNC6671's (Cordial Spider) adversary-in-the-middle vishing operation running since April under five extortion brands, with more than $8 million across 15 Bitcoin wallets, an average of $600,000 per payment, and 78 phishing sub-domains across 76 organizations, 40% in financial services.

The Hacker News · 29d agoThreat actor in the wild1