New Go-Based JaskaGO Malware Targeting Windows and macOS Systems

Cyber Threat Summary:
AT&T Alien Labs has uncovered a new Go-based information stealer malware dubbed JaskaGo designed to target both Windows and Apple macOS systems. According to researchers, the info-stealer comes equipped with an extensive array of commands from its C2 server that enable actors to execute shellcode, enumerate running processes, harvest information from the victim system, and download additional payloads. Upon execution, the malware is capable of checking whether it is running within a virtualized environment. If detected, JaskaGo will run a harmless task to prevent suspicion. Researchers also note that the malware is capable of stealing data from web browsers and modifying the clipboard, enabling actors to conduct cryptocurrency theft by substituting wallet addresses.

Security Officer Comments:
It is unclear what form of distribution method is employed by actors to spread JaskaGO. Researchers note that some of the samples were observed masquerading as AnyConnect and security tools. As such the actors could be using phishing or malvertising lures to infect potential victims.

The use of Go-based malware is not novel. Many actors have created go-based malware variants, due to the simplicity of the language and its cross-platform capabilities. Given that JaskaGo is capable of targeting macOS systems, this increases the number of victims susceptible to potential attacks.

Suggested Correction(s):
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.