Alert: Water Curupira Hackers Actively Distributing PikaBot Loader Malware

Water Curupira, a threat actor, distributed the Pikabot loader malware in spam campaigns throughout 2023. Trend Micro reported that PikaBot’s phishing attacks used a loader and a core module to gain remote access and execute commands via a connection to their server. This activity occurred from Q1 to June, earlier campaigns by cybercrime group TA571 and TA577 targeting victims with Qakbot.

This surge in PikaBot attacks followed the takedown of Qakbot in August, with DarkGate emerging as its replacement. Pikabot’s main purpose is to launch other payloads like Cobalt Strike, often proceeding ransomware deployment. The attacks utilized email thread hijacking with ZIP attachments containing JavaScript or IMG files to initiate PikaBot. The malware checks for Russian or Ukrainian languages on systems to avoid execution. Information about victims’ sent to a C&C server in JSON format.

Security Officer Comments:
Water Curupira’s campaigns aimed to deploy Cobalt Strike, leading to Black Basta ransomware. While DarkGate and IcedID campaigns were initially conducted, the focus shifted solely to PikaBot later in the third quarter of 2023, according to Trend Micro. Additionally, Trend Micro’s report highlighted Water Curupira’s transition from DarkGate and IcedID campaigns to exclusively focusing on PikaBot during the early weeks of the third quarter of 2023.

Suggested Corrections:

Users should always be cautious of individuals or organizations that ask for personal information. Most companies will not ask for sensitive data from its customers. If in doubt, users should verify with the company itself to avoid any potential issues.

Users should always take a close look at the sender’s display name when checking the legitimacy of an email. Most companies use a single domain for their URLs and emails, so a message that originates from a different domain is a red flag.

As a general rule, users should not click links or download files even if they come from seemingly “trustworthy” sources.

Check for mismatched URLs. While an embedded URL might seem perfectly valid, hovering above it might show a different web address. In fact, users should avoid clicking links in emails unless they are certain that it is a legitimate link.

Users should always be on the lookout for any grammatical errors and spelling mistakes. Legitimate companies will often employ proofreaders and editors who ensure that the materials they send out are error-free.

Users should not be frightened or intimidated by messages that have an alarmist tone. They should double check with the company if they are uncertain about the status of their accounts.

Phishing emails are designed to be sent to a large number of people, so they need to be as impersonal as possible. Users should check whether the message contains a generic subject and greeting, as this can be a sign of a phishing attempt.

Although not every end user has access to advanced anti-phishing software, they can still use the built-in protection of their email clients to filter messages. One example is setting the email client to block all images unless approved.

Legitimate companies will never send confirmation emails unless there are specific reasons for doing so. In fact, most companies will avoid sending unsolicited messages unless it’s for company updates, newsletters, or advertising purposes.

Users should always take the context of an email or message into account. For example, most online accounts do away with viewable member numbers, so users should be wary if they receive emails containing a “member number” for services that generally don’t use them.

It is important to take note of unusual information in the text of the message. Any mentions of operating systems and software that are not typically used by consumers can often be indicators of a phishing attempt.

If it seems suspicious, it probably is. Users should always err on the side of caution when it comes to sending out personally identifiable information through messages and emails.