Introduction
Spear phishing and email fraud are the most efficient methods for hackers to begin a data breach
A malicious hacker, whether a cybercriminal or a state actor, deploys deceptive sender information to a targeted victim and deceives the recipient into either installing malware or disclosing sensitive private information.
The outcome may be ravaging for an enterprise that falls victim to such sneaky attacks. Moreover, it costs companies, regardless of their size, millions in revenue loss and lawsuits. Significantly, money isn’t solely the issue. Brand name damage to the company makes it extremely difficult to recover.
DMARC is an acronym for Domain-Based Message Authentication, Reporting & Conformance which serves as the security standard for email security to prevent against spear phishing and email fraud. Nonetheless, numerous businesses are either unmindful of its perilous presence or baffled by how DMARC can stop attacks.
What A Spoofed Email Message From An Attacker Looks Like
To know how DMARC works from a security perspective, it is significant first to grasp how email fraud works. A malicious hacker will initially conduct reconnaissance during the early stage of a cyber attack without the victim knowing.
In the reconnaissance stage, the adversary will carry out a search and review the employees of a business or government.
For example, LinkedIn serves as not merely an effective social media platform for cyber actors, but also a powerful tool that may be used to gather information regarding a corporation during reconnaissance as employees are interconnected under one corporation. The hacker may obtain valuable information regarding an organization and discover targeted vulnerable users using escalated privileges.
When the attacker acquires a list of targeted users, the subsequent step is to spoof the email messages. The fundamental essence of a spoofed email message is one whereby the sender’s address appears similar to an official email address, though it’s actually fabricated by the attacker.
Many email users are conversant with email client software such as Mozilla Thunderbird that automatically adds a sender address on the basis of software configurations. The email client transmits a message, employing the configured email account for the sender address.
Outgoing email servers operate services that grab an email sender’s address, recipient address, metadata pertaining text subject, and body and transmits it to the target recipient email server. Such service operates publicly on an email server, and it may be misused by hackers provided that no authentication is needed.
Publicly reachable email servers that lack authentication requirements are deployed by globally resourceful adversaries to send spoofed messages. A hacker sends the servers an email message utilizing a sender address recognizable to the targeted victim. Evidently, the unfortunate victim may be an individual within a company or a third-party vendor.
In the absence of email security, the message is dispatched to the consumer with the fraudulent sender address, and if the adversary succeeds, the recipient may be fooled into sending confidential information or downloading malware that provides the hostile actor access to the local computer.
How DMARC Works
DMARC refers to an assortment of security rules that are established to validate a legitimate email address and quarantine messages that fail substantiation.
It is configured on an institution’s email server employing two security standards. The first is the Sender Policy Framework (SPF) which confirms the sender’s IP (Internet Protocol) address.
Secondly, the DomainKeys Identified Mail (DKIM) utilizes encrypted digital signatures to corroborate the sender’s domain.
The first element of DMARC security is SPF entries on the sender’s DNS (Domain Name System) servers.
Despite the fact that hostile actors may fabricate a sender’s address, they cannot counterfeit the IP address from the original sender device.
For every server hop in an email message route to the recipient’s server, the IP address is logged in the message headers which allows investigators to examine the contents digitally. Consumers cannot read email headers to ascertain a spoofed message. Hence, they require email security applications that accomplish it for them. SPF filters email on the basis of the sender IP.
Once an organization determines the precise moment to apply DMARC, it ought to add approved IPs on DNS servers. Published SPF records on the sender’s DNS server supply an enumeration comprising sanctioned IP addresses for the enterprise’s email servers.
Solely sanctioned IP addresses will pass DMARC security rules. Once a DMARC-enabled email server acquires a message, it carries out an SPF entry lookup to validate that the IP address in email headers is permitted. If the IP is not permitted, the message will be quarantined immediately.
DKIM Serves As The Second Element Of DMARC Security
DKIM stands for DomainKeys Identified Mail which is the second element of DMARC security. DKIM employs asymmetric encryption and digital signatures. Comprehending DKIM requires you to grasp the technique revolving how public and private key encryption work.
Private keys are utilized to sign messages that merely the company’s public key may decrypt. Private keys must never be shared, revealed, or published anywhere. The company’s public key is declared as TXT records on the DNS server.
While DMARC-enabled email server circulates a message, it employs its private key to produce a digital signature in the shape of a hash. The digital signature is affixed to the email headers and dispatched to the recipient email server.
Once the recipient’s email server receives a message, it fetches the public key saved on the sender’s DNS server and decrypts the digital signature. It further proceeds to compute a freshly encrypted signature deploying the sender’s public key.
In the event that the value in the digital signature matches up with the freshly computed signature, then the email is regarded as genuine, and it goes right into the recipient’s inbox.
Security Advice For Companies
As we can see, using DMARC can prevent spear phishing and email fraud. Email security is tremendously important.
Corporations that fail to have the DMARC security standard implemented risk having their companies’ valuable information stolen by malicious hackers.
External adversaries aren’t the only ones they exist. Insider threats within an organization also exist and stopping such threats is critical to preventing data breaches. Implementing various layers of protection is key to defeating hackers.
Keep in mind that employees sharing data with each other within a company is also risky, and there are multiple measures and considerations that ought to be considered.
Not only can systems of organizations be compromised, but hackers can potentially take control of a company’s domain if proper security measures are not adopted by the target.
Employees of various companies must refrain from publicly sharing their personal information on the internet which cyberspies are continually using to their advantage for purposes of espionage and financial gain.
Security intrusion from clicking on malware within email attachments can be minimized when simple tips are followed. Nonetheless, companies continue to disregard such steps which ultimately lead to their downfall disastrous.
Email users can better protect themselves by cautiously examining each email they receive. More importantly, companies of any size should train their employees to detect spear phishing attempts and email fraud.
Companies of any size should hire professional penetration testers to conduct various types of penetration testing to protect their organizations from malicious hackers.
