Relating to spam, we often consider a bunch of completely irrelevant promoting letters, which antispam engines filter out with no hassle in any respect. Nevertheless, that is removed from essentially the most disagreeable factor that may fall into your mailbox. Generally spam is used to hold out a DDoS assault on company e mail addresses, and the sufferer will get bombarded with utterly official emails that don’t increase any suspicion of a typical antispam engine.
Registration confirmations assault
As a way to carry out a mail bomb assault, attackers can exploit the registration mechanisms on the internet sources of completely unrelated corporations. Utilizing automation instruments, they register on hundreds of companies from completely different nations utilizing the sufferer’s e mail deal with. Consequently, an enormous variety of confirmations, hyperlinks to activate your account, and related letters find yourself in your mailbox. Furthermore, since they’re despatched by official mail servers with repute, the antispam engine considers them authorized and doesn’t block them.
Examples of registration affirmation emails used for DDoS assaults on company e mail addresses
As a goal the attackers often select an deal with that’s essential for the corporate’s work — one thing that’s used to speak with shoppers or companions; for instance, a mailbox of the gross sales division, technical assist, or a financial institution’s deal with to which functions for mortgage loans are despatched. An assault can final for days, and the plethora of emails merely overload the sufferer’s mail server and paralyze the work of the attacked division.
To efficiently shield a mailbox from such an assault, a extra refined software is required. As one of many approaches to safety in opposition to mail bombs, we suggest utilizing the customized content material filtering module constructed into our up to date Kaspersky Safe Mail Gateway Specifically, within the above instance of an assault via registration mechanisms, the operator can block letters based mostly on the presence of the phrase “registration” in varied languages within the Topic discipline (Registrace | Registracija | Registration | Registrierung | Regisztráció). Consequently, emails shall be mechanically despatched to quarantine with out reaching the inbox and overloading the mail server.
Personalised mail filter settings
In Kaspersky Safe Mail Gateway model 2.1 we’ve added the next choices for filtering incoming and outgoing mail:
- by letter dimension;
- by attachment varieties and names;
- by sender — you\’ll be able to specify a particular sender deal with or a daily expression;
- by recipients (together with hidden ones);
- by the presence of sure textual content within the physique of the letter (key phrases and common expressions might be added to the dictionary);
- by the presence of textual content within the topic of the letter – by key phrases, utilizing masks and common expressions, indicating particular senders;
- by X-headers.
Versatile filtering of enterprise mailings
The brand new capabilities of our resolution can be utilized not solely to guard in opposition to e mail bombs assaults. They can be utilized, for instance, for versatile configuration of B2B-mailout filtering. Not all workers understand every kind of enterprise mailings in the identical method: for some it is smart to delve into provides to buy digital parts; for others such commercials simply clog up their inboxes, whereas they take into account varied invites to take part in conferences or conduct seminars extraordinarily beneficial.
Due to this fact, utterly blocking official enterprise mailouts isn’t an possibility. However alternatively, it’s additionally not value permitting their uncontrolled supply: somebody will at all times be dissatisfied. Due to this fact, Kaspersky Safe Mail Gateway doesn’t categorize such letters as spam, however permits you to configure their versatile filtering by senders, recipients, textual content within the topic or physique of the letter, and so forth.
You possibly can study extra about Kaspersky Safe Mail Gateway, a part of Kaspersky Safety for Mail Servers resolution on our company web site.