CyberDudeBivash DeepDive — New Gmail Phishing Attack: Weaponized Login Flow Steals Credentials By CyberDudeBivash — ruthless, engineering-grade threat intel

 


🚨 Executive Summary

Attackers are running a new Gmail phishing campaign that abuses a weaponized login flow to harvest credentials and bypass traditional security controls. Unlike conventional phishing kits, this attack leverages legitimate-looking Google authentication flows embedded with malicious redirections, creating high-trust deception for victims.

Impact:

  • Theft of Gmail/Workspace credentials.

  • Potential compromise of SSO-linked enterprise accounts.

  • Risk of supply-chain breaches through Google Drive/Docs sharing.


🔎 Attack Flow Breakdown

  1. Initial Vector — Email Lure

    • Victims receive a phishing email disguised as:

      • Google Drive file share

      • Security notification (“Your account will be disabled”)

      • Invoice/HR notifications with embedded login links.

  2. Weaponized Login Redirect

    • The link leads to a crafted login portal hosted on compromised or attacker-controlled infrastructure.

    • Attackers use embedded OAuth flows or Google-styled HTML templates.

  3. Credential Harvesting

    • Once the victim enters email + password, credentials are captured.

    • In some cases, the phishing kit also prompts for 2FA codes or attempts Adversary-in-the-Middle (AitM) interception.

  4. Post-Exploitation

    • Stolen credentials are used to:

      • Access Gmail/Workspace.

      • Hijack Google Drive/Docs for further phishing (“reply-chain phishing”).

      • Move laterally into enterprise accounts tied to Google SSO.


🎯 Why This Attack Works

  • High-trust deception: Pages mimic legitimate Google login workflows.

  • Real branding: Embedded icons, certificates, and “https://” hosting tricks.

  • Multi-step flow: Victims are led through what feels like a real Gmail sign-in, reducing suspicion.

  • AitM capability: Captures MFA tokens in real-time.


🛡️ Detection & Defense

Indicators of Attack (IOAs)

  • Emails with links to non-Google domains (but disguised with docs.google.com text).

  • Login prompts served from compromised WordPress, Shopify, or static site hosts.

  • Shortened links (bit.ly, tinyurl) pointing to “Google login.”

Defender Actions

  1. Email Gateway Rules:

    • Block messages with “Google login” text but non-Google domains in URLs.

  2. Browser Security Controls:

    • Enable Safe Browsing and reputation-based URL filtering.

  3. MFA Hardening:

    • Promote FIDO2/WebAuthn keys instead of SMS or app-based OTPs (mitigates AitM).

  4. User Awareness:

    • Train users to always verify auth URLsaccounts.google.com.


⚡ Threat Hunting Queries

Splunk — Suspicious OAuth Logins

index=google_workspace sourcetype=gsuite:login | search LoginType="OAuth" | where not like(ClientApp, "%Google%") | table _time, User, ClientApp, IPAddress

Elastic KQL — MFA Bypass Attempts

event.dataset : "gsuite.login" and outcome.result : "Success" and source.ip : ("suspicious ranges") and authentication.type : "MFA"

🛠️ Incident Response Steps

  1. Reset compromised accounts immediately.

  2. Invalidate OAuth tokens tied to suspicious apps.

  3. Review email forwarding rules (attackers often set persistence here).

  4. Search for reply-chain phishing from compromised mailboxes.

  5. Rotate sensitive credentials linked to Google SSO.


📌 CyberDudeBivash Verdict

This Gmail phishing wave is next-gen social engineering, blending weaponized login flows with real-time MFA bypass. Enterprises relying on Google Workspace should treat this as high priority, enforce phishing-resistant MFA, and deploy email + browser detection controls immediately.

#CyberDudeBivash #Phishing #Gmail #GoogleWorkspace #CredentialTheft #ThreatIntel #BlueTeam #IncidentResponse #AitM #ZeroTrust

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