Avoid losing your email account via fake "Mailbox Quota Exceeded" emails

What kind of email is "Mailbox Quota Exceeded"?

"Mailbox Quota Exceeded" is a phishing spam campaign. We inspected two email variants belonging to this campaign. Both versions inform recipients that their email account storage quota has been exceeded and needs to be increased.

When attempts are made to update the account, users get redirected to a phishing website disguised as an email sign-in page.

"Mailbox Quota Exceeded" email scam overview

The spam email with the subject "De-activation of Mailbox [recipient's_email_address]" (may vary) states that the mail account has run out of storage and cannot receive any more messages. The fake letter instructs to increase the quota and receive undelivered emails by clicking the "AUTO-EXPAND STORAGE" button.

The email with the subject "Email Verification" (may vary) likewise informs the recipient that their mail account has reached its storage limit, which it lists as 99.9 GB. The recipient is warned that unless they validate their account again within 48 hours, they will be blocked from sending/receiving emails. To verify the account and add storage, the letter instructs the recipient to click the link presented in it.

It must be emphasized that these emails are fake, as is all the information they provide. Hence, when the button/link is pressed – it results in a redirect to a phishing website. This site is presented and an email account sign-in webpage.

Data (i.e., email address and password) entered into the phishing website – will be disclosed to the scammers behind this spam campaign. In addition to stealing the exposed mail accounts, cyber criminals may also hijack the content registered through them.

To elaborate on how scammers can misuse this unauthorized access, they can assume the identities of social account owners (e.g., emails, social media/networking, messengers, etc.) and ask the contacts/friends/followers for loans or donations, promote scams, and even proliferate malware by sharing malicious files/links. While stolen finance-related accounts can be used to make fraudulent transactions and online purchases.

To summarize, by trusting a spam email – users can experience system infections, severe privacy issues, significant financial losses, and even identity theft.

If you have provided your account credentials to a phishing website – immediately change the passwords of all potentially exposed accounts and contact their official support.

Threat Summary:

Name	"Mailbox Quota Exceeded" phishing email
Threat Type	Phishing, Scam, Social Engineering, Fraud
Fake Claim	Recipient's mailbox storage quota has been reached; emails cannot be received/sent.
Related Domains	muenchnernotizen[.]info
Detection Names (muenchnernotizen[.]info)	Avira (Phishing), Combo Cleaner (Malware), CRDF (Malicious), CyRadar (Malicious), Emsisoft (Phishing), ESET (Phishing), Full List Of Detections (VirusTotal)
Serving IP Address (muenchnernotizen[.]info)	172.67.155.14
Symptoms	Unauthorized online purchases, changed online account passwords, identity theft, illegal access of the computer.
Distribution methods	Deceptive emails, rogue online pop-up ads, search engine poisoning techniques, misspelled domains.
Damage	Loss of sensitive private information, monetary loss, identity theft.
Malware Removal (Windows)	To eliminate possible malware infections, scan your computer with legitimate antivirus software. Our security researchers recommend using Combo Cleaner. ▼ Download Combo Cleaner To use full-featured product, you have to purchase a license for Combo Cleaner. 7 days free trial available. Combo Cleaner is owned and operated by Rcs Lt, the parent company of PCRisk.com read more.

Phishing spam campaign examples

"Intesa Sanpaolo email scam", "Social Security Account Missing Information", "You Have Delayed Messages", and "ETH (Ethereum) Giveaway" are merely some examples of phishing emails we have inspected recently.

Spam letters are used to facilitate a wide variety of scams, and they are even employed in malware proliferation. These emails can be disguised as "official", "urgent", "priority", and so on; they can even be presented as messages from legitimate service providers, companies, organizations, authorities, and other entities.

How do spam campaigns infect computers?

Spam emails can contain malicious files as attachments or download links. These files can be in various formats, e.g., documents (PDF, Microsoft Office, Microsoft OneNote, etc.), executables (.exe, .run, etc.), archives (RAR, ZIP, etc.), JavaScript, and so forth.

When a virulent file is executed, run, or otherwise opened – the malware download/installation process is triggered. For example, Microsoft Office documents infect devices by executing malicious macro commands. While infectious Microsoft OneNote documents need users to click embedded content.

How to avoid installation of malware?

We strongly recommend exercising caution with incoming emails, DMs/PMs, SMSes, and other messages. The attachments and links found in dubious mail must not be opened, as they can be virulent. It is important to use Microsoft Office versions released after 2010 since they have the "Protected View" mode that prevents automatic macro command execution.

It must be mentioned that malware is not distributed exclusively via spam mail. Therefore, we also advise being careful when browsing since fake and malicious online content usually appears harmless.

Another recommendation is to download only from official and verified channels. It is crucial to activate and update software using genuine functions/tools, as illegal activation tools ("cracks") and third-party updaters can contain malware.

We must stress the importance of having a dependable anti-virus installed and kept up-to-date. Security programs must be used to run regular system scans and to remove threats and issues. If you've already opened malicious attachments, we recommend running a scan with Combo Cleaner Antivirus for Windows to automatically eliminate infiltrated malware.

Text presented in a variant of the "Mailbox Quota Exceeded" spam email letter:

Subject: De-activation of Mailbox -

Mailbox Quota Exceeded

Hi ********,

Your email ******** is out of storage and can not receive more mails.

Kindly add storage quota to your mailbox from below portal to receive your undelivered mails.

AUTO-EXPAND STORAGE

For more enquiries, visit our Help Center  or call +1 (877) 509-8177.

We hope to serve you better.

Regards,
******** IT Team.
_______________________________________________________

&© All Rights Reserved. Cpanel Webmail 1995-2023.

Screenshot of another variant of the "Mailbox Quota Exceeded" spam email:

Text presented in this email variant:

Subject: Email Verification

Mailbox Quota Exceeded

Dear -,
 
Your email has used up the storage limit of 99.9 gigabytes as defined by your Administrator. You will be blocked from sending and receiving messages if not re- validated within 48hrs.
Kindly click on your email below for quick re-validation and additional storage will be updated automatically

-

 
Regards,
E-mail Support 2023.

Screenshot of the phishing website promoted by the "Mailbox Quota Exceeded" spam campaign:

Instant automatic malware removal: Manual threat removal might be a lengthy and complicated process that requires advanced IT skills. Combo Cleaner is a professional automatic malware removal tool that is recommended to get rid of malware. Download it by clicking the button below:
▼ DOWNLOAD Combo Cleaner By downloading any software listed on this website you agree to our Privacy Policy and Terms of Use. To use full-featured product, you have to purchase a license for Combo Cleaner. 7 days free trial available. Combo Cleaner is owned and operated by Rcs Lt, the parent company of PCRisk.com read more.

Quick menu:

• What is "Mailbox Quota Exceeded" phishing email?
• Types of malicious emails.
• How to spot a malicious email?
• What to do if you fell for an email scam?

Types of malicious emails:

Phishing Emails

Most commonly, cybercriminals use deceptive emails to trick Internet users into giving away their sensitive private information, for example, login information for various online services, email accounts, or online banking information.

Such attacks are called phishing. In a phishing attack, cybercriminals usually send an email message with some popular service logo (for example, Microsoft, DHL, Amazon, Netflix), create urgency (wrong shipping address, expired password, etc.), and place a link which they hope their potential victims will click on.

After clicking the link presented in such email message, victims are redirected to a fake website that looks identical or extremely similar to the original one. Victims are then asked to enter their password, credit card details, or some other information that gets stolen by cybercriminals.

Emails with Malicious Attachments

Another popular attack vector is email spam with malicious attachments that infect users' computers with malware. Malicious attachments usually carry trojans that are capable of stealing passwords, banking information, and other sensitive information.

In such attacks, cybercriminals' main goal is to trick their potential victims into opening an infected email attachment. To achieve this goal, email messages usually talk about recently received invoices, faxes, or voice messages.

If a potential victim falls for the lure and opens the attachment, their computers get infected, and cybercriminals can collect a lot of sensitive information.

While it's a more complicated method to steal personal information (spam filters and antivirus programs usually detect such attempts), if successful, cybercriminals can get a much wider array of data and can collect information for a long period of time.

Sextortion Emails

This is a type of phishing. In this case, users receive an email claiming that a cybercriminal could access the webcam of the potential victim and has a video recording of one's masturbation.

To get rid of the video, victims are asked to pay a ransom (usually using Bitcoin or another cryptocurrency). Nevertheless, all of these claims are false - users who receive such emails should ignore and delete them.

How to spot a malicious email?

While cyber criminals try to make their lure emails look trustworthy, here are some things that you should look for when trying to spot a phishing email:

• Check the sender's ("from") email address: Hover your mouse over the "from" address and check if it's legitimate. For example, if you received an email from Microsoft, be sure to check if the email address is @microsoft.com and not something suspicious like @m1crosoft.com, @microsfot.com, @account-security-noreply.com, etc.
• Check for generic greetings: If the greeting in the email is "Dear user", "Dear @youremail.com", "Dear valued customer", this should raise suspiciousness. Most commonly, companies call you by your name. Lack of this information could signal a phishing attempt.
• Check the links in the email: Hover your mouse over the link presented in the email, if the link that appears seems suspicious, don't click it. For example, if you received an email from Microsoft and the link in the email shows that it will go to firebasestorage.googleapis.com/v0... you shouldn't trust it. It's best not to click any links in the emails but to visit the company website that sent you the email in the first place.
• Don't blindly trust email attachments: Most commonly, legitimate companies will ask you to log in to their website and to view any documents there; if you received an email with an attachment, it's a good idea to scan it with an antivirus application. Infected email attachments are a common attack vector used by cybercriminals.

To minimise the risk of opening phishing and malicious emails we recommend using Combo Cleaner Antivirus for Windows. 

Example of a spam email:

What to do if you fell for an email scam?

• If you clicked on a link in a phishing email and entered your password - be sure to change your password as soon as possible. Usually, cybercriminals collect stolen credentials and then sell them to other groups that use them for malicious purposes. If you change your password in a timely manner, there's a chance that criminals won't have enough time to do any damage.
• If you entered your credit card information - contact your bank as soon as possible and explain the situation. There's a good chance that you will need to cancel your compromised credit card and get a new one.
• If you see any signs of identity theft - you should immediately contact the Federal Trade Commission. This institution will collect information about your situation and create a personal recovery plan.
• If you opened a malicious attachment - your computer is probably infected, you should scan it with a reputable antivirus application. For this purpose, we recommend using Combo Cleaner Antivirus for Windows.
• Help other Internet users - report phishing emails to Anti-Phishing Working Group, FBI’s Internet Crime Complaint Center, National Fraud Information Center and U.S. Department of Justice.

Frequently Asked Questions (FAQ)

Why did I receive this email?

Spam emails are not personal. They are distributed in massive operations – therefore, thousands of users receive identical messages.

I have provided my personal information when tricked by this spam email, what should I do?

If you have disclosed your log-in credentials – change the passwords of all potentially exposed accounts and inform their official support without delay. And if the revealed data was of a different personal nature (e.g., ID card details, credit card numbers, etc.) – immediately contact relevant authorities.

I have read a spam email but didn't open the attachment, is my computer infected?

No, merely opening an email will not result in a system infection. Malware download/installation processes are jumpstarted when malicious attachments or links are opened/clicked.

I have downloaded and opened a file attached to a spam email, is my computer infected?

If the opened file was an executable (.exe, .run, etc.) – most likely, yes – your device was infected. However, you might have avoided triggering an infection if it was a document (.doc, .xls, .one, .pdf, etc.). These formats may require additional user interaction (e.g., enabling macro commands, clicking embedded files/links, etc.) to start downloading/installing malware.

Will Combo Cleaner remove malware infections present in email attachments?

Yes, Combo Cleaner is designed to detect and eliminate threats. It can remove practically all known malware infections. However, it must be stressed that running a full system scan is essential – since sophisticated malicious software usually hides deep within systems.

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