Spammer techniques: how do they exploit e-mail?
Estimated reading time: 9 minutes
Spam seems to reach every single email account we use , no matter how careful we are or what the address provider is. How do spammers get all of our email addresses? Can we do something to hide our email address from common spammer techniques?
Unfortunately, there’s not much you can do to stop spammers from bombarding you with emails. There are some tips that will help protect you, but spammers will probably find your email address anyway .
The problem is not so much the unwanted advertisement message, but rather what it means that you received a message. How did you react? Did you delete it? Did you click on any links? Have you flagged it as spam? Any action could bring useful information to attackers without you noticing.
Let’s face it more clearly and start with a question: where do spammers find our e-mails?
Spammer techniques for retrieving e-mail addresses
Nobody gives their email to a website and expects it to end up in the hands of a scammer. Yet it’s not uncommon for someone to find their inbox full of unsolicited spam emails.
The simplest of the techniques spammers use to collect large lists of active email addresses is through stolen account databases. These password thefts happen with frightening regularity. Companies like Adobe, LinkedIn, eHarmony, Gawker, Last.fm, Yahoo !, Snapchat and Sony have all been compromised in recent years .
Leaked databases are normally considered a security threat because they often display account names and passwords. However, generally show email addresses as well. Spammers can download these leaked databases and add the millions of email addresses to their lists . Spammers know that most of these email addresses should be active , so these databases are excellent for them.
This is probably how most spammers are finding email addresses to send spam. There really isn’t much you can do to protect yourself from a spammer who gets your address this way.
A site like Have I been pwned? can tell you if the information of your account may have been spread .
You can protect yourself from password theft by using different ones, unfortunately, you must always use the same email address everywhere , it would be unthinkable to have an address for each service used.
Link in mail messages
If you receive spam emails, you should avoid clicking on the links in the email . If you find an “Unsubscribe” link in an email from a legitimate company, it’s probably safe to click it. A real company doesn’t want to spam and potentially run into anti-spam laws, so they will simply remove you from their list.
However, if you see an “Unsubscribe” link (or, even worse, a “Buy Now!” link) in an email that looks very unprofessional and scam, the spammer will not necessarily remove you from his lists .
This is where things get more complex. They will notice your click and their systems will identify your email address as active . They know you’re there, and you may see larger amounts of spam after clicking the link.
The same goes for uploading images in spam emails. Do not click the “Upload images” button, or spammers will know that you have opened the email . Even if you don’t see an image in the message, there may be a small tracking pixel that allows the spammer to identify you if you upload the asset.
This is why most email clients don’t automatically upload images.
E-mail scraping, search for unencrypted e-mails on the net
Another spammer technique to retrieve addresses from the network is to scrape them ( scraping ) from the unencrypted data on the network. There are software out there that read files on the net and find those that contain e-mails and save them. A bit like Google’s crawlers do when they crawl a site, but with malicious intent.
You may have seen a comment where someone leaves their address to be contacted. The bot that scans the network will save similar addresses.
The spammer adds this address to his spam lists et voilà , spam is served . This is why eBay provides a temporary email address where you can be reached rather than including your real email address. This technique is probably less common now that spammers have huge leaked account databases to work with.
Spammers can also try to acquire valid email addresses by browsing other places that are publicly available, such as whois records for a domain . These records show an email address associated with the person or organization that registered the domain name.
Purchase of email addresses
Another spammer technique, definitely for lazy hackers, is to buy addresses from databases that provide them.
Unscrupulous people sell email lists to spammers for a low price. These addresses were often distributed on CD in the past , and may still be, but the leaked account databases have probably eliminated some interest in this market.
Spammers can also simply exchange their mailing lists with each other, making sure other bad guys get their hands on your address once it happens the first time.
Please be aware that this technique is not entirely illegal. When we subscribe to a service, we often have the possibility to provide our e-mail address to third parties for advertising purposes. Some users accept without reflection and without verifying whether it is an obligation to subscribe to the service or not. .
I personally happened to be contacted by a person who, with no intent to spam, but to make up the number, had bought my address from a contact resale agency, divided by areas of interest. If he had been a spammer, he could have used a similar service.
How to protect your address
Spammers can also obtain email addresses in other ways but the methods listed above are some of the most common.
There isn’t much you can do to prevent your email address from being leaked and receiving spam.
- – you can avoid putting your e-mail address on the web in plain text form
- – never click on a link
- – don’t upload a image in a suspicious email.
However, your address will almost certainly end up in the hands of a spammer at some point.
Actually, you don’t have to worry so much about whether the address is in circulation, but about how the address is used, especially if it is active.
Spammer techniques of using addresses
Once a scammer obtains your email address, it is very likely that they will use it to take advantage in any way possible . The better he is, the greater the risks.
Many will send you spam emails, with the hope of collecting private information such as credit card numbers . They will try to trick you into believing that you have won something, or that they have a profitable item for sale. Hackers may also use your email to steal your identity and send messages to your contacts . Remember the techniques of Zombie Phishing ?
Other scammers will use your personal information to try to access your other accounts . Most people reuse the same passwords for different accounts, which means that hackers who have access to one account can easily infiltrate the others.
This is why using the same passwords around the web is highly discouraged and not secure at all.
One of the reasons why you should never actively interact with spam messages is that interactions send hackers an important piece of information: the address is active, someone uses it on their device.
An active address, once discovered, is a perfect target for more specific attacks than phishing , and since all addresses are at risk, even corporate ones, from phishing you can easily get to a double extortion ransomware .
In the latter case, the threat of a DDoS attack may already come from mentioned zombie phishing technique, and it could all have started with some spam message.
The computers that will basically send requests to the server to perform the DDoS attack could themselves be part of a botnet created as a result of techniques used by spammers .
Phenomenology of an attack
As a first spammer technique, company addresses are retrieved . This can be done through scraping or database buying on the dark web. Next, to check which addresses are active , a couple of spam campaigns are sent. Nothing harmful, fake newsletters with an obvious Unsubscribe message, or a tracking pixel.
Note: A tracking pixel is usually a very small transparent image that is uploaded from a remote server. Just check how many times it has been downloaded and by whom to understand which addresses are active and which are not .
As a result, the contact database will have shrunk to a list of active addresses , in which users have been inattentive enough to click on a link from a suspicious email.
Finally, to these selected addresses, is sent a real phishing message containing malware or a request to intervene on a seemingly legitimate web page . For example, the request to reset your credentials via the attached link.
The unsuspecting user, thinking he is doing a safe thing, follows the link, enters the credentials and gives them to the spammer . At this point the attacker has gained access to an account. From that moment on, the risks are much more and much more damaging.
How to defend against spammer techniques
Let’s take a few steps back. The whole chain of events that led the hacker to gain access to an important account went through spam and phishing messages.
In some of the passages, the attack could have been avoided . The ability to recognize a suspicious message and then ignore it is the first weapon available to a user. SOD can help your business with this .
Through a ethical phishing service, we first test the resilience of users . Once any weak points have been identified, a training course ad hoc is constructed to provide adequate proactive defense tools to all employees.
SOC as a Service
Not always being aware users is enough , and a careless mistake could cost a company a lot of sensitive data. For this reason, we can also implement a service SOCaaS for the mitigation of risk and damage following an attack.
In this scenario, a system consisting of next generation SIEM and protocols UEBA implemented by an artificial intelligence, they monitor the network in search of any anomaly . Any suspicious behavior is identified and analyzed by technicians to see if it can actually become a threat or not.
If you would like more information on how SOD can help you raise your company’s cybersecurity level, don’t hesitate to contact us.
- Hadoop Open Data Model: “open” data collection
- Pass the Ticket: how to mitigate it with a SOCaaS
- Use cases of a SOCaaS for companies part 2
- Use cases of a SOCaaS for companies part 1
- NIST Cybersecurity Framework
- “Left of boom” and “right of boom”: having a winning strategy
- Smishing: a fraud similar to phishing
- Network Traffic Analyzer: an extra gear for the Next Gen SIEM
- Backup as a Service (2)
- Cloud Conference (3)
- Cloud CRM (1)
- Cloud Server/VPS (20)
- Conferenza Cloud (4)
- ICT Monitoring (4)
- Log Management (2)
- News (18)
- ownCloud (4)
- Privacy (7)
- Secure Online Desktop (14)
- Security (14)
- Web Hosting (15)
- Armis Now Valued at $3.4B November 29, 2021One Equity Partners led the $300 million round, increasing the valuation of Armis from the $2 billion valuation it achieved less than 8 months ago.
- Stellar Cyber Raises $38M Series B to Address Need to Provide 360-Degree Visibility Across Entire Attack Surface November 29, 2021Oversubscribed round, including Samsung, rewards technical innovations and rapid market adoption, positions company for continued leadership.
- 9 out of 10 Healthcare Organizations Provide Telehealth Services, Yet Almost Half Face Patients' Mistrust Toward Privacy November 29, 2021Kaspersky surveyed healthcare decision-makers to learn how the digital transformation of the industry is going and which problems they believe should be solved to create a world in which everyone can gain access to quality care.
- IKEA Email Systems Targeted in Cyberattack November 29, 2021Attackers are reportedly targeting IKEA employees in a phishing campaign that leverages stolen reply-chain emails.
- Google Analyzes Methods Behind GCP Workload Attacks November 29, 2021The vast majority of cloud workload compromises stem from poor security configurations or compromised passwords, while cryptojacking is the common payload, research shows.
- Phishing Remains the Most Common Cause of Data Breaches, Survey Says November 29, 2021Despite heightened concerns over ransomware, fewer organizations in a Dark Reading survey reported being an actual victim of a ransomware attack over the past year.
- Over 1,000 Individuals Arrested in Global Cybercrime-Fighting Operation November 29, 2021HAECHI-II initiative represents Interpol's stepped-up efforts to tackle the operators of financially motivated online scams and other cyberattacks.
- Panasonic Hit in Data Breach November 29, 2021Tech firm reveals that data on one of its file servers was accessed by attackers.
- NanoLock Security and Waterfall Security Partner to Deliver OT Security for Industrial and Energy Applications November 29, 2021The solution combines NanoLock’s device-level, zero-trust protection with Waterfall’s hardware-enforced IT/OT perimeter protection to provide a powerful OT security solution that mitigates cyber events from both IT and OT networks.
- Paving the Road to Zero Trust With Adaptive Authentication November 29, 2021A gradual transition to a world beyond passwords predisposes zero-trust projects to success.
- Re: Responsible Full disclosure for LiquidFiles 3.5.13 November 23, 2021Posted by Riccardo Spampinato on Nov 23Dear Full Disclosure Team, This is to ask you to kindly update our responsible disclosure. Following the updated advisory. =============================================================================== title: LiquidFiles Privilege Escalation product: LiquidFiles v3.5.13 vulnerability type: Privilege Escalation severity: High CVSSv3 score: 8.8 CVSSv3 vector:...
- Backdoor.Win32.BlueAdept.02.a / Remote Buffer Overflow November 21, 2021Posted by malvuln on Nov 21Discovery / credits: Malvuln - malvuln.com (c) 2021 Original source: https://malvuln.com/advisory/694d21679cc212c59515584d1b65dc84.txt Contact: malvuln13 () gmail com Media: twitter.com/malvuln Threat: Backdoor.Win32.BlueAdept.02.a Vulnerability: Remote Buffer Overflow Description: The malware listens on TCP port 6969, after connecting to the infected host TCP ports 6970, 6971 are then opened. The newly opened port 6970 […]
- Backdoor.Win32.BNLite / Remote Heap Based Buffer Overflow November 21, 2021Posted by malvuln on Nov 21Discovery / credits: Malvuln - malvuln.com (c) 2021 Original source: https://malvuln.com/advisory/a8818da39c7d36d9b5497d1a875798b8.txt Contact: malvuln13 () gmail com Media: twitter.com/malvuln Threat: Backdoor.Win32.BNLite Vulnerability: Remote Heap Based Buffer Overflow Description: The malware listens on TCP port 5000. Third party attackers who can reach the system can send a specially crafted payload to trigger […]
- Backdoor.Win32.Agent.ad / Insecure Credential Storage November 21, 2021Posted by malvuln on Nov 21Discovery / credits: Malvuln - malvuln.com (c) 2021 Original source: https://malvuln.com/advisory/d2b933ebadd5c808ca4c68ae173e2d62.txt Contact: malvuln13 () gmail com Media: twitter.com/malvuln Threat: Backdoor.Win32.Agent.ad Vulnerability: Insecure Credential Storage Description: The malware listens on TCP port 87, its default password "hoanggia" is stored in the Windows registry in cleartext under "clrprv.oo" in...
- Backdoor.Win32.Wollf.h / Hardcoded Cleartext Password November 21, 2021Posted by malvuln on Nov 21Discovery / credits: Malvuln - malvuln.com (c) 2021 Original source: https://malvuln.com/advisory/5494b78dcfaf16aa43b5dbd563dc5582.txt Contact: malvuln13 () gmail com Media: twitter.com/malvuln Threat: Backdoor.Win32.Wollf.h Vulnerability: Hardcoded Cleartext Password Description: The malware listens on TCP port 7300 and runs with SYSTEM integrity. Authentication is required for remote user access. However, the password "grish5800" is...
- Backdoor.Win32.Wollf.a / Weak Hardcoded Password November 21, 2021Posted by malvuln on Nov 21Discovery / credits: Malvuln - malvuln.com (c) 2021 Original source: https://malvuln.com/advisory/52d1341f73c34ba2638581469120b68a.txt Contact: malvuln13 () gmail com Media: twitter.com/malvuln Threat: Backdoor.Win32.Wollf.a Vulnerability: Weak Hardcoded Password Description: The malware listens on TCP port 1698 and runs with SYSTEM integrity. Authentication is required for remote user access. However, the password "23706373" is weak...
- Backdoor.Win32.Antilam.11 / Unauthenticated Remote Command Execution November 21, 2021Posted by malvuln on Nov 21Discovery / credits: Malvuln - malvuln.com (c) 2021 Original source: https://malvuln.com/advisory/290477c9707f64a316888493ae67b1ef.txt Contact: malvuln13 () gmail com Media: twitter.com/malvuln Threat: Backdoor.Win32.Antilam.11 Vulnerability: Unauthenticated Remote Command Execution Description: The malware listens on TCP ports 29559, 47891. Third party attackers who can reach infected systems can execute commands made available by the backdoor....
- Backdoor.Win32.Curioso.zp / Insecure Permissions November 21, 2021Posted by malvuln on Nov 21Discovery / credits: Malvuln - malvuln.com (c) 2021 Original source: https://malvuln.com/advisory/1ae08493913b2a0c8cbcb0541da5a8bc.txt Contact: malvuln13 () gmail com Media: twitter.com/malvuln Threat: Backdoor.Win32.Curioso.zp Vulnerability: Insecure Permissions Description: The malware creates a dir with insecure permissions under c:\ drive granting change (C) permissions to the authenticated user group. Standard users can rename the...
- Backdoor.Win32.Acropolis.10 / Insecure Permissions November 21, 2021Posted by malvuln on Nov 21Discovery / credits: Malvuln - malvuln.com (c) 2021 Original source: https://malvuln.com/advisory/e865fc7225c84165d7aa0c7d8a1bcb77.txt Contact: malvuln13 () gmail com Media: twitter.com/malvuln Threat: Backdoor.Win32.Acropolis.10 Vulnerability: Insecure Permissions Description: The malware writes an .EXE with insecure permissions under c:\ drive granting change (C) permissions to the authenticated user group. Standard users can rename the...
- Open-Xchange Security Advisory 2021-11-19 November 21, 2021Posted by Open-Xchange GmbH via Fulldisclosure on Nov 21Dear subscribers, we're sharing our latest advisory with you and like to thank everyone who contributed in finding and solving those vulnerabilities. Feel free to join our bug bounty programs for OX AppSuite, Dovecot and PowerDNS at HackerOne. Yours sincerely, Martin Heiland, Open-Xchange GmbH Product: OX App […]
Tempo di lettura: 5 minUtilizzo del Machine Learning per proteggere i dati Introdotto nel gennaio 2017, Acronis Act… https://t.co/mhqalBxm8D
Gli attacchi informatici sono numerosi e non fanno distinzione tra aziende e singoli individui quando prendono di m… https://t.co/uOucUWZf7W
Estimated reading time: 5 minutes SNYPR è uno strumento di analisi della sicurezza in grado di trasformare i Big… https://t.co/oies7e0nYY
Estimated reading time: 5 minutes Con l’avvento delle piattaforme di big data, le aziende che si occupano di sicu… https://t.co/MSvA0dPgiE
Estimated reading time: 5 minutes With the advent of big data platforms, IT security companies can now make guid… https://t.co/aTv41eq2Ir