Almost half of all organisations have fallen victim to phishing attacks in the last two years, with larger businesses the most likely to been compromised, despite also being most likely to conduct cyber security training for staff.
Research by security company Sophos has found that 45 percent of UK organisations were compromised by phishing attacks between 2016 and 2018 — and that 54 percent had identified instances of employees replying to unsolicited emails or clicking the links in them.
Phishing emails are a common attack technique deployed in hacking campaigns, with hackers attempting to lure victims into downloading malware or entering sensitive credentials into a phoney version of a website, such as a bank, a retailer, or a fake login page of the target organisation's own email system.
The attacks sound simple, but they're often deployed as the first step in campaigns by groups ranging from cyber-criminal gangs looking to make money, to nation-state-backed hacking groups looking to conduct espionage or cause disruption.
Even if there hasn't been any immediate or obvious damage, there's the potential for attackers to have gained persistent access to target networks, especially if the victim hasn't done anything to counter the attack.
"It's difficult to assess how successful attacks are being exploited. It could be anything from simple credential theft to a network compromise leading to a data breach and everything in between," John Shier, senior security expert at Sophos told ZDNet.
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There's also the potential that the attackers could gain further ground if there are instances of password re-use by the victim, which is why security professionals recommend that multi-factor authentication is applied across the enterprise.
"Regardless of the end goal, it's important to understand that once a cyber criminal has your credentials, as far as the authentication systems know, they are you. This is why two-factor authentication is a must for all your accounts," said Shier.
While cyber criminals attack organisations of all sizes, the Sophos study — undertaken by Sapio Research — suggests that it's larger organisations that are more likely to fall victim to a phishing attack: 54 percent of organisations with between 500 and 1,000 employees have fallen victim to phishing in the past two years.
That figure drops to 39 percent for firms with 250 to 500 staff, and drops again to just 14 percent for businesses with under 250 people. While smaller firms are often said to be easier targets for hackers, it's likely that cyber criminals looking for a lucrative payday will be focusing their attentions on large organisations.
However, with the threat that phishing poses, it's not something that any organisation of any size can afford to ignore — and senior executives should ensure their business has processes in place to attempt to prevent it from happening, as well as providing proper channels for employees to report suspected attacks.
"The reality is that 100 percent of organisations will be faced with fending off phishing attacks and unfortunately many attacks will succeed. Knowing that you've been compromised and reacting quickly is paramount," said Shier.
"Not only should organisations urge their users to report potential phishing attacks but also encourage a safe reporting environment for when users make a mistake," he added.
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