Hackers Exploit Salesforce Zero-Day to Run Phishing Campaign

Guardio Labs security researchers uncovered a new, unpatched exploit in Salesforce email servers that resulted in an advanced email phishing campaign. The vulnerability allowed hackers to craft phishing emails under the company's email servers and domain, which were then used to target Facebook users.

The attack, dubbed PhishForce, is impressively elusive, engineered to bypass the detection systems of both Salesforce and Facebook. The strategy entails sending malicious emails and concealing them within trustworthy mail gateways, which are usually free of any blocklists. Then, the victims are led to a phishing page hosted on the Facebook platform itself, giving the impression that it’s legitimate.

The investigation was initiated by the researchers when they spotted a single suspicious email, referencing the actual name of the targeted user. The email seemed to originate from 'Meta Platforms' and was dispatched allegedly from an @salesforce.com address.

The objective of the email was to lead users to a deceptive landing page that aims to steal the target's account credentials. What sets this attack apart is that the phishing page is camouflaged as a game on the Facebook apps platform, allowing it to exist under the Facebook domain undetected.

Guardio's analysis found that attackers targeted Salesforce CRM's Email Gateway component, specifically exploiting the 'Email-To-Case' feature. This allowed them to receive verification emails, eventually giving them control over a genuine Salesforce email address.

For Facebook, the phishing page was hosted on a legacy web games platform. According to SecurityWeek, the attackers gained access to an account associated with one of these games and used it to host their phishing page. Meta is currently investigating how their usual protections against this kind of malicious activity failed to work.

Guardio informed Salesforce on June 28th, and within a month, a fix was applied to all affected services, preventing the use of Salesforce domain addresses for email sending. Salesforce confirmed no evidence of customer data impact.