MailGuard has intercepted a phishing campaign using deceptive email alerts to harvest user credentials. This particular scam is designed to look like a legitimate warning that a user’s mailbox is nearly full, urging recipients to “manage storage settings” via a spoofed interface. The goal is to trick users into entering their credentials on a fake login page, enabling cybercriminals to hijack their email accounts.
What the scam looks like
The phishing email, titled “Your Mailbox is 99% Full,” falsely claims that the recipient's email storage is at 95% capacity and risks deactivation. It features an urgent call to action with a “Manage Storage Settings” button, a lure to direct recipients to a credential-harvesting site.
Here's what the email looks like 👇
Clicking the button redirects users to a fake login page, which mimics an official webmail service but is hosted on a malicious domain unrelated to the recipient’s email provider.
Once users enter their email address, they are prompted for a password.
Upon submission, the interface displays a fake “Signing In…” message, suggesting background activity, which may include credential exfiltration.
Technical Observations from MailGuard’s Threat Intelligence Team
Credential phishing attacks like this one are especially dangerous for businesses. A single compromised account can lead to widespread damage, including unauthorised access to sensitive data, internal fraud, or even ransomware deployment. These threats often bypass traditional filters by impersonating trusted domains or leveraging low-complexity HTML tactics that evade automated detection.
Technique: Simple HTML email containing a phishing link. The recipient’s email address is embedded into the phishing URL as a parameter.
Flow:
- Initial confirmation screen.
- Email address and password entry.
- Fake “Signing In…” message.
Sender Details:
- Display name: The recipient’s own domain (a common tactic to gain trust).
- Sender address: `d002719(at)avas(dot)sggw(dot)pl`, not a legitimate source.
Threat Type: Phishing
Target: Email account credentials
Stay Safe - Know the Signs
MailGuard advises all recipients of these emails to delete them immediately without clicking on any links. Responding or providing personal details can lead to identity theft, data breaches, and financial losses.
Avoid emails that:
- Aren’t addressed to you personally.
- Are unexpected and urge immediate action.
- Contain poor grammar or miss crucial identifying details.
- Direct you to a suspicious URL that isn’t associated with the genuine company.
Many businesses turn to MailGuard after a near miss or incident. Don't wait until it's too late. Reach out to our team for a confidential discussion by emailing expert@mailguard.com.au or calling 1300 30 44 30.
One Email Is All That It Takes
All that it takes to devastate your business is a cleverly worded email message that can steal sensitive user credentials or disrupt your business operations. If scammers can trick one person in your company into clicking on a malicious link or attachment, they can gain access to your data or inflict damage on your business.
For a few dollars per staff member per month, you can protect your business with MailGuard's specialist, 'zero zero-day' email security. Special Ops for when speed matters! Our real-time 'zero zero-day', email threat detection amplifies our client’s intelligence, knowledge, security and defence. Talk to a solution consultant at MailGuard today about securing your company's inboxes.
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