Threat Signal Report

Mac Malware UpdateAgent Variant Distributed Through Drive-by-download

description-logo Description

FortiGuard Labs is aware of a report that a variant of UpdateAgent disguised as legitimate software was distributed in the wild. UpdateAgent (a.k.a WizardUpdate) is a macOS malware that is typically used to collect information from the compromised machine and install unwanted apps on it such as adware. According to Microsoft who reported the latest campaign, UpdateAgent is likely being delivered via drive-by-downloads, a term that refers to the unintentional download of malicious code onto a computer or mobile device without any user interaction or consent.


Why is this Significant?

This is significant because UpdateAgent has reportedly received several updates over the past year for new features such as evading the macOS GateKeeper and installing additional payloads off the public cloud infrastructure. The developer is expected to continue the upgrade effort as one of the main goals of the malware is financial gain through the adware it deploys.


What is UpdateAgent?

UpdateAgent (aka WizardUpdate) is a malware for macOS that is designed to harvest information from the compromised machine. UpdateAgent has gained additional features such as installing additional payloads by abusing legitimate public cloud infrastructures and bypassing GateKeeper. Microsoft claims UpdateAgent was first discovered in November/December 2020.


How is UpdateAgent Distributed?

UpdateAgent is typically distributed through fake software (e.g., a fake Flash Player). Microsoft states that UpdateAgent was distributed via drive-by-downloads in the recent campaign. Drive-by-download refers to the unintentional download of malicious code onto a computer or mobile device without any user interaction or consent.


What is GateKeeper?

GateKeeper is a security feature offered by Apple for macOS, which is designed to ensure that only trusted software runs on the machine. The feature relies on code-signing verification and blacklists of known malware.


What is the Status of Coverage?

FortiGuard Labs provide the following coverage against the UpdateAgent variant Microsoft called out and older variants FortiGuard Labs was able to find:

MAC/Agent.8AC3!tr

MAC/Agent.5753!tr

MAC/Agent.E3CB!tr

Adware/Agent!OSX


Definitions

Traffic Light Protocol

Color When Should it Be used? How may it be shared?

TLP: RED

Not for disclosure, restricted to participants only.
Sources may use TLP:RED when information cannot be effectively acted upon by additional parties, and could lead to impacts on a party's privacy, reputation, or operations if misused. Recipients may not share TLP:RED information with any parties outside of the specific exchange, meeting, or conversation in which it was originally disclosed. In the context of a meeting, for example, TLP:RED information is limited to those present at the meeting. In most circumstances, TLP:RED should be exchanged verbally or in person.

TLP: AMBER

Limited disclosure, restricted to participants’ organizations.
Sources may use TLP:AMBER when information requires support to be effectively acted upon, yet carries risks to privacy, reputation, or operations if shared outside of the organizations involved. Recipients may only share TLP:AMBER information with members of their own organization, and with clients or customers who need to know the information to protect themselves or prevent further harm. Sources are at liberty to specify additional intended limits of the sharing: these must be adhered to.

TLP: GREEN

Limited disclosure, restricted to the community.
Sources may use TLP:GREEN when information is useful for the awareness of all participating organizations as well as with peers within the broader community or sector. Recipients may share TLP:GREEN information with peers and partner organizations within their sector or community, but not via publicly accessible channels. Information in this category can be circulated widely within a particular community. TLP:GREEN information may not be released outside of the community.

TLP: WHITE

Disclosure is not limited.
Sources may use TLP:WHITE when information carries minimal or no foreseeable risk of misuse, in accordance with applicable rules and procedures for public release. Subject to standard copyright rules, TLP:WHITE information may be distributed without restriction.