Remove “Mailbox Error Detected” email

The “Mailbox Error Detected” email falls into the phishing category. The email is disguised as a notification from your email service provider, and it informs you that an error has been detected in your mailbox. To continue using your email account, you supposedly need to click on the provided link and log in to your account. However, this email is part of a phishing campaign, and the link will lead you to a phishing site. If you were to type in your password on this site, it would be sent to the malicious actors behind this phishing campaign. This could allow them to get into your email account if it’s not protected by multi-factor authentication.

 

 

The “Mailbox Issue Identified” email is supposed to mimic an alert from the email service provider, but it’s a rather poor attempt. It falsely informs you that an error has been detected in your mailbox and that you need to log in to your account to continue receiving/sending emails. The email has a “Login Now” button that redirects you to a phishing website designed to mimic an official email service provider site, in this case, Gmail. The phishing site has a similar design, but more vigilant users should be able to immediately identify it as a phishing site because not only does the URL not match, but it also displays an additional login pop-up that you wouldn’t get on the legitimate Gmail site. If login credentials are entered on this phishing site, they are stolen, granting cybercriminals access to the email account if no additional security measures (e.g., multi-factor authentication) are in place.

Email credentials are very valuable to malicious actors, as they can provide access to extensive personal information and are often linked to multiple other accounts. A compromised email account can result in the hijacking of numerous connected accounts, which is why it’s so important that users are very careful with their login credentials, particularly for important accounts.

Victims of this phishing attack should immediately change their passwords if they still have access to their email accounts. If access is lost and recovery options are unsuccessful, disconnecting the compromised email address from all associated accounts is essential to prevent further account hijacking.

The full “Mailbox Issue Identified” email phishing email is below:

Subject: undelivered emails-Account Verification Required

Mailbox Error Detected

User: – ,

We detected an error in your mailbox –

To ensure continued communication to receive/send emails, please log in immediately to resolve this issue.

Login Now

Please note that this email was automatically generated by the system, so there is no need to reply.

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Signs of a phishing email

Phishing campaigns that use generic emails to target a large number of users are usually easy to spot. More sophisticated phishing campaigns tend to target specific, usually high-profile users or organizations, and they require a greater level of effort and personalization. These tailored emails can appear very convincing, potentially catching even the most vigilant users off guard. Fortunately, regular users are unlikely to be targets of these sophisticated emails. And as long as users know what to look for, they can often identify these deceptive emails with relative ease.

If you get an unsolicited email that demands immediate action, such as clicking a link or downloading an attachment, always verify the sender’s email address first. In this case, it’s obvious the “Mailbox Error Detected” email was not sent by your email service provider, as the sender’s email address does not use a Gmail domain, nor does it look professional enough to come from a legitimate sender. In less sophisticated phishing attempts, the sender’s address may stand out as suspicious, as it could be completely random. However, some attackers use clever techniques to make their email addresses look at least somewhat more legitimate, like substituting letters (for example, using “rn” instead of “m”) or adding extra characters to mimic trusted sources.

A very obvious sign of a malicious email is grammar and spelling mistakes. For whatever reason, malicious and phishing emails are full of them. A lot of those emails are also worded quite awkwardly and unnaturally, as is the case with the “Mailbox Error Detected” email. It’s very important that users take their time when reviewing emails and not rush to click on links or open attachments. Any unsolicited attachments should be scanned with antivirus software or checked on VirusTotal to confirm that they are not harmful before opening. And users should avoid clicking on links altogether. Instead, they should access their accounts manually.