Hackers hijack hotel Wi-Fi DNS to steal Microsoft 365 accounts

Summary

Attackers are compromising Wi-Fi gateways in hotels and conference centers to redirect users to fake Microsoft 365 login pages, potentially stealing corporate credentials. The campaign, observed since June across various industries and global regions, may be linked to APT28. The attackers exploit DNS settings and can bypass MFA using a device-code authentication flow.

Full text

Hackers hijack hotel Wi-Fi DNS to steal Microsoft 365 accounts By Bill Toulas July 24, 2026 01:50 PM 0 Hackers are changing the DNS settings on Wi-Fi devices at hotels and conference centers to redirect users to fake Microsoft 365 login pages. The campaign has been ongoing since at least June and impacts organizations in various sectors, including financial services, professional services, legal, health care, energy, and retail. Cybersecurity company ReliaQuest identified compromised Wi-Fi gateways in multiple U.S. cities as well as other regions of the world, such as India and Saudi Arabia. Since the devices serve corporate events, hijacking the Microsoft 365 accounts could give attackers access to sensitive business information, communications, and private documents. “We observed traffic to these compromised gateways from organizations in a range of industries, including financial services, professional services, legal, health care, energy, and retail- confirming this isn't sector-specific targeting, but a campaign that highly likely goes after traveling employees wherever they connect,” ReliaQuest says. The researchers believe this activity is similar to the FrostArmada router-based campaigns attributed to the Russian espionage group APT28 (a.k.a. Fancy Bear, Forest Blizzard). Attack chain It is unclear how initial access to the Wi-Fi appliances was gained, but ReliaQuest says the threat actor could have exploited weakly protected, exposed management interfaces (e.g., SSH, SNMP, web admin dashboards) or vulnerabilities. Once the attacker gains administrator access, they can modify the gateway’s DNS settings to redirect connections to legitimate domains to infrastructure under the attacker's control. ReliaQuest says that the attacker registered at least four domains for setting up fake Microsoft login portals: m365-owa[.]com, owa-ms365[.]com, ms365-device[.]com, and ms365-live[.]com. With DNS settings changed, users trying to access legitimate Microsoft login portals would land on the hacker's phishing pages and enter their credentials. In some cases, the researchers observed a device-code authentication flow in which targets were redirected to a fake Microsoft page with a prompt. "What the user can't see is that approving the prompt authorizes a session initiated by the attacker," ReliaQuest says. The researchers note that authorizing the attacker-initiated request causes a legitimate OAuth token to be issued to the attacker's client. This bypasses the multi-factor authentication (MFA) protection without stealing any credentials or intercepting access tokens. The attack stepsSource: ReliaQuest In roughly one-third of the investigated cases, the attackers also attempted to abuse Web Proxy Auto-Discovery (WPAD) by responding to Windows' automatic WPAD lookup with a malicious proxy auto-configuration (PAC) file. This theoretically would route traffic from Windows apps, including Chrome, through an attacker-controlled proxy, but ReliaQuest couldn’t confirm that these attacks were successful. The researchers also emphasized that using public DNS servers such as Google’s 8.8.8.8 does not prevent this attack, as the gateway forges the plain-text requests before they reach the intended resolver. ReliaQuest recommends using an always-on, full-tunnel VPN and encrypted DNS in strict mode as solid protection measures against these attacks. Additionally, the cybersecurity company recommends disabling WPAD, reviewing logs for suspicious activity, and disabling Device Code authentication flow in Microsoft Entra ID when not needed. Test every layer before attackers do Security teams log 54% of successful attacks and alert on just 14%. The rest move through your environment unseen.The Picus whitepaper shows how breach and attack simulation tests your SIEM and EDR rules so threats stop slipping by detection. Get the whitepaper Related Articles: New Forg365 phishing platform uses AI to target Microsoft 365 accountsNew phishing kits target Microsoft 365 accounts, evade MFAARToken PhaaS exposes EvilTokens' Microsoft 365 phishing toolkitEntra passkey enrollment vishing targets Microsoft 365 usersWebinar tomorrow: Why modern email attacks require a new approach to defense

Indicators of Compromise

• domain — m365-owa[.]com
• domain — owa-ms365[.]com
• domain — ms365-device[.]com
• domain — ms365-live[.]com

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