ReliaQuest’s threat research team just documented attackers compromising the Wi-Fi gateways at hotels and conference centers, then quietly rerouting guests toward fake Microsoft login pages. No phishing email required. No malicious attachment. Just bad luck about which hotel you picked.
“Adversaries have been compromising public Wi-Fi gateways at hotels, conference centers, and other shared venues to hijack the accounts of traveling corporate employees.” reads the report published by ReliaQuest. “Once they control the Wi-Fi gateway, they quietly redirect users to attacker-controlled infrastructure to steal credentials, in activity ongoing since at least June 2026.”
The mechanism is simple once you see it. These gateways handle DNS for every device that connects, so whoever controls the gateway controls where your traffic actually goes, even when the address bar looks completely normal. ReliaQuest found compromised devices across several US cities plus India and Saudi Arabia, hitting employees from finance, law, healthcare, energy, and retail, which tells you this isn’t aimed at one industry. It’s aimed at anyone who travels for work.
Researchers think the entry point was weak or reused admin credentials on internet-facing management interfaces, things like exposed SSH or web consoles.
“ReliaQuest assesses with low-to-medium confidence that initial access into these devices exploited exposed management interfaces (including internet-facing SSH, SNMP, and web administration consoles) in combination with weak or reused administrative credentials.” continues the report. “We encountered visibility constraints into the individual devices that prevented confirmation of this hypothesis, but this methodology would be consistent with the gateway targeting and DNS poisoning patterns documented in recent reporting on an APT28-linked campaign known as “FrostArmada.””
Once inside, the attackers pointed DNS toward domains built to look like Microsoft’s login pages, including m365-owa.com and ms365-live.com. The whole thing runs on trust, since a device joining a network just assumes the DNS resolver it’s handed is telling the truth.
That trust gets abused in a way that dodges the DNS protections people already have. Switching to a hardcoded resolver like 8.8.8.8 doesn’t save you, because the query still leaves the laptop unencrypted and the gateway can rewrite the answer before it ever reaches Google’s server. Encrypted DNS tools help only if they run in strict mode; the default “opportunistic” mode quietly falls back to plaintext the moment encryption fails, and that fallback is exactly what gets hijacked.
“Two configurations do stop it. A full-tunnel VPN routes all DNS through the corporate tunnel before the gateway can touch the request. Encrypted DNS in strict mode (DNS over HTTPS or DNS over TLS with plaintext fallback disabled) ensures the gateway can’t forge a response.” states the cybersecurity firm. “Most DNS encryption tools default to opportunistic mode, which permits plaintext fallback when encrypted resolution fails. That fallback is what the gateway redirects, making opportunistic mode insufficient; only strict mode closes the gap.”
ReliaQuest also caught something extra in about a third of cases: an attempt to abuse Windows’ automatic proxy discovery feature, known as WPAD.
WPAD is a Windows feature that automatically discovers proxy settings when a device connects to a network. In this campaign, attackers abused it by controlling DNS responses, potentially tricking Windows into loading a malicious proxy configuration. If successful, they could intercept traffic from browsers, authentication services, and enterprise apps. Because the traffic still uses HTTPS, the attack can blend in with normal network activity and be difficult to detect.
Pull that off and the attacker routes a much wider slice of an employee’s traffic, not just login attempts, through their own proxy. In a smaller number of cases, the attackers skipped credential theft entirely and went after Microsoft’s device-code sign-in flow instead, tricking users into approving a login they didn’t realize belonged to someone else. Approve that prompt and the attacker walks away with a valid, MFA-cleared session token, no password needed.
“In roughly one-third of observed cases—Windows devices that didn’t have Web Proxy Auto-Discovery (WPAD) disabled, or Mac devices—the attacker also attempted WPAD abuse. If successful, it routes all Windows application traffic through the attacker’s proxy, broadening the redirection surface well beyond authentication traffic.” continues the report. “This technique wasn’t documented in prior FrostArmada-linked reporting, making it one of the clearest distinctions between this campaign and previously observed APT28 activity.”
There’s a pattern connecting all this to previous campaigns. The tradecraft echoes a Russian-linked operation called FrostArmada, which hit home routers the same way earlier this year, and researchers tie both to the group known as APT28 (aka UAC-0001, aka Fancy Bear, Pawn Storm, Sofacy Group, Sednit, BlueDelta, and STRONTIUM). The link isn’t a smoking gun; it’s shared technique, not shared infrastructure, and the researchers say so plainly.
The fix is almost boringly simple, which is rare in this line of work. Force every corporate device onto an always-on VPN with full-tunnel routing, so DNS never touches the hotel network at all, and shut off split-tunnel exceptions that would let it sneak through anyway. Disable WPAD where nobody needs it, block Microsoft’s device-code flow at the identity provider unless someone has a real reason to keep it, and train people to check the certificate before they type a password on airport or hotel Wi-Fi.
None of this requires new budget or a six-month project. It requires someone actually flipping the switches that already exist.
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