Why the FBI is warning the world about spear-phishing attacks

Spear-phishing is one of the main tools used by attackers to compromise endpoints and gain a foothold in the enterprise network. The issue has been deemed serious enough for the FBI to a deliver a warning about the worrying rise in spear-phishing, and multiple industry sectors have fallen foul of the attacks all over the world.

In spear-phishing scams, cyber-criminals utilise a specially crafted email message that entices users to perform an action that will result in a drive-by download, data theft, or both. Compromising systems and grabbing login credentials of employees enables the attacker to access corporate resources. This is why spear-phishing is often the first step used to enable Advance Persistent Threats (APTs) and targeted attacks.

You can’t blame the user

In the past, it was believed that proper user education would prevent phishing attacks. However, despite the significant time and resources invested in education programs, spear-phishing attacks continue to be successful. This is not only because enterprise users can be naïve and careless. This is mainly because attackers use information gained through social engineering to personalise the spear-phishing messages and convince targeted users that the message is legitimate.

As the FBI warning explains, “Often, the e-mails contain accurate information about victims obtained via a previous intrusion or from data posted on social networking sites, blogs, or other websites. This information adds a veneer of legitimacy to the message, increasing the chances the victims will open the e-mail and respond as directed.”

It is impossible to prevent enterprise users from opening email attachments or following links since it is a routine part of their everyday activity. As long as our lives are dependent on online information, spear-phishing will remain a threat.

Endpoints used as gateway to network

Spear-phishing emails often result in drive-by downloads: a silent malware download that takes place in the background, without the user’s awareness. Drive-by downloads are enabled by vulnerabilities in user applications like browsers (or browser plug-ins), Java applications, Adobe Acrobat and more. Exploiting unpatched, or unknown, zero-day vulnerabilities, attackers can download malware to the user’s machine while the user remains unaware of the download.

The attacker can then use a compromised device to gain access to the corporate network, steal intellectual property and compromise operational systems and/or financial assets. The FBI explains that, “In spear-phishing attacks, cyber criminals target victims because of their involvement in an industry or organisation they wish to compromise.”

Protect all login credentials

Attackers also use phishing sites - fake websites designed to look like the real application login site - in order to convince users to submit their credentials. If a user is fooled to submit corporate credentials on a phishing site, the attacker can exploit those to access corporate applications and other resources.

In order to effectively stop spear-phishing attacks, organisations must prevent drive-by downloads and protect enterprise credentials. What’s required are security solutions which minimise the exploitation of application vulnerabilities, block information theft, prevent attackers from gaining remote control over employee endpoints, and ensure that enterprise users do not submit and expose their credentials on phishing sites.

Dana Tamir is director of enterprise security at Trusteer.

Image: Flickr (infocux Technologies)