Newly discovered Vigilante malware outs software pirates and blocks them

A warning sign on a grid-style metal fence.

A researcher has uncovered one of many extra uncommon finds within the annals of malware: booby-trapped recordsdata that rat out downloaders and attempt to stop unauthorized downloading sooner or later. The recordsdata can be found on websites frequented by software program pirates.

Vigilante, as SophosLabs Principal Researcher Andrew Brandt is calling the malware, will get put in when victims obtain and execute what they assume is pirated software program or video games. Behind the scenes, the malware stories the file identify that was executed to an attacker-controlled server, together with the IP tackle of the victims’ computer systems. As a of completion, Vigilante tries to change the victims’ computer systems to allow them to not entry thepiratebay.com and as many as 1,000 different pirate websites.

Not your typical malware

“It’s actually uncommon to see one thing like this as a result of there’s usually only one motive behind most malware: stealing stuff,” Brandt wrote on Twitter. “Whether or not that’s passwords, or keystrokes, or cookies, or mental property, or entry, and even CPU cycles to mine cryptocurrency, theft is the motive. However not on this case. These samples actually solely did just a few issues, none of which match the standard motive for malware criminals.”

As soon as victims have executed the trojanized file, the file identify and IP tackle are despatched within the type of an HTTP GET request to the attacker-controlled 1flchier[.]com, which may simply be confused with the cloud-storage supplier 1fichier (the previous is spelled with an L because the third character within the identify as a substitute of an I). The malware within the recordsdata is essentially equivalent apart from the file names it generates within the net requests.

Vigilante goes on to replace a file on the contaminated pc that stops it from connecting to The Pirate Bay and different Web locations recognized for use by folks buying and selling pirated software program. Particularly, the malware updates Hosts, a file that pairs a number of area addresses to distinct IP addresses. Because the picture under reveals, the malware pairs thepiratebay.com to 127.zero.zero.1, a special-purpose IP tackle, typically known as the localhost or loopback tackle, that computer systems use to establish their actual IP tackle to different methods.

Sophos

By mapping the domains to the native host, the malware ensures that the pc can not entry the websites. The one solution to reverse the blocking is to edit the Hosts file to take away the entries.

Brandt discovered a few of the trojans lurking in software program packages obtainable on a Discord-hosted chat service. He discovered others masquerading as well-liked video games, productiveness instruments, and safety merchandise obtainable by means of BitTorrent.

There are different oddities. Most of the trojanized executables are digitally signed utilizing a faux code signing instrument. The signatures include a string of randomly generated 18-character uppercase and lowercase letters. The certificates validity started on the day the recordsdata grew to become obtainable and is about to run out in 2039. Moreover, the properties sheets of the executables don’t align with the file identify.

When seen by means of a hex editor, the executables additionally include a racial epithet that’s repeated greater than 1,000 instances adopted by a big, randomly sized block of alphabetical characters.

“Padding out the archive with purposeless recordsdata of random size might merely be finished to change the archive’s hash worth,” Brandt wrote. “Padding it out with racist slurs instructed me all I wanted to find out about its creator.”

Vigilante has no persistence technique, which means it has no solution to stay put in. Meaning individuals who have been contaminated want solely to edit their Hosts file to be disinfected. SophosLabs gives indicators of compromise here.