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Showing posts with label Chrome Extensions. Show all posts

Malicious Operations Hide Under The Google Chrome Sync Feature

 

Lately, the threat actors have detected a technique where they can use the sync feature of Google Chrome to transmit commands and steal data from infected systems, circumvent conventional firewalls and other network protections to infected browsers. Chrome sync is a Chrome browser feature that stores copies of a Chrome user's bookmarks, browsing history, browser passwords, and extension settings on Google's cloud servers. This function is used to synchronize the aforementioned data with various devices of a user so that the user still has access to his new Chrome information everywhere. 

On Thursday 4th of January, Bojan Zdrnja, a Croatian security researcher, shared his discovery, wherein a malicious Chrome extension exploited the Chrome sync as a way to connect with a remote command and control (C&C) server and to exfiltrate the details from compromised browsers during the latest incident reaction. 

In addition, Zdrnja added that the attackers had gotten access to a victim's device during the incident he investigated, however, because the data they tried to steal was inside the worker's portal, therefore they downloaded Chrome extension on the user’s system and loaded it in Developer's Mode. It included malicious code that abused Chrome's synchronized functionality to allow attackers to monitor the infected browser, which was used as a security add-on by security company Forcepoint. 

Zdrnja claimed that the purpose of this unique attack was to use the extension to "manipulate data in an internal web application that the victim had access to." 

"While they also wanted to extend their access, they actually limited activities on this workstation to those related to web applications, which explains why they dropped only the malicious Chrome extension, and not any other binaries," Zdrnja stated in a report. 

"In order to set, read or delete these keys, all the attacker has to do is log in with the same account to Google, in another Chrome browser (and this can be a throwaway account), and they can communicate with the Chrome browser in the victim's network by abusing Google's infrastructure," he added, wherein data stored in the key field could be anything. For instance, data obtained from the infected browser may be malicious extensions or commands the attacker desires to run the extension at an infected workstation (for example, usernames, passwords, cryptographic keys, or more).

Although the stolen content or corresponding commands are transmitted via Chrome's infrastructure, no process can be inspected or blocked in the majority of corporate networks, which are normally authorized to run and transfer data unimpeded by the Chrome browser. 

The researcher recommended businesses to use Chrome company and community decision assistance to block and monitor the plugins that could be installed on a browser, prohibiting rogue extensions, such as the one he investigated, from being installed.

Attention! Fake Extensions on the Chrome Web Store Again!


Reportedly, Google was in the news about having removed 49 Chrome extensions from its browser’s store for robbing crypto-wallet credentials. What’s more, after that, there surfaced an additional set of password-swiping “extensions” aka “add-ons”, which are up for download even now.

Per sources, the allegedly corrupt add-ons exist on the browser store disguised as authentic crypto-wallet extensions. These absolutely uncertified add-ons invite people to fill in their credentials so as to make siphoning off them easy and the digital money accessible.

Reports mention that the security researchers have affirmative information as to 8 of the 11 fake add-ons impersonating legitimate crypto-wallet software being removed including "Jaxx Ledger, KeyKeep, and MetaMask." A list of “extension identifiers” which was reported to Google was also provided.

Per researchers, there was a lack of vigilance by the Google Web Store because it apparently sanctions phisher-made extensions without giving the issue the attention it demands. Another thing that is disturbing for the researchers is that these extensions had premium ad space and are the first thing a user sees while searching.

According to sources, much like the Google Play Store with malicious apps, the Google Web Store had been facing difficulty in guarding itself against mal-actors. There also hadn’t been much of a response from their team about the issue.

One solution that was most talked about was that Google should at the least put into effect mechanisms in the Chrome Web Store that automatically impose trademark restrictions for the store and the ad platforms in it.

Per sources, Google’s Chrome Web Store “developer agreement” bars developers from violating intellectual property rights and also clearly mentions “Google is not obligated to monitor the products or their content”. Reports mention that as per the ad policy of Google, it could review trademarks complaints from trademarks holders only when it has received a complaint.

Google heeding all the hue and cry about the extensions did herald more restrictions with the motive of wiping away traces of any fake extensions and spammers creating bad quality extensions that were causing people trouble.

The alterations in the policy will block the spammers and developers from swarming the store with similar extensions and elements with questionable behavior. Word has it that because of hateful comments the Chrome Web Store was “locked down” in January.

But, as promising as it may be, allegedly Google has been making such promises about the Chrome Web Store security strengthening for more than half a decade. So no one can blame researchers for their skepticism.

"CursedChrome", a chrome extension used by hackers to make your browser into a proxy


Security researchers have found a Chrome extension that turns Chrome browsers in proxy bots that enables the hacker to browse chrome using an infected identity.
This tool was created by Matthew Bryan, a security researcher, he named it "Cursed Chrome" and released it on GitHub as an open-source project.

 The software works on two fronts and has two parts -

  • a client-side component (this is the chrome extension) 
  • a server-side counterpart ( this is where all CursedChrome server report) 
Once this extension is installed, it can be used to log into the CursedChrome control panel, and through it, the hacker can use any infected browser. Thus, the hacker can navigate and browse the net using that identity and can even access logged in sessions and credentials.

This extension is the icing on the cake for hackers and has been received with skepticism. Many at the cybersecurity community have raised their eyebrows at the public release of such software saying it's nothing short of handing a gun to a killer to do the killing. 

Created for Pen-testing

The creator, Matthew Bryant says that his intentions were quite innocent. "I open-sourced the code because I want other professional red teamers and pen-testers to be able to accurately simulate the 'malicious browser-extension' scenario," says Bryant in a statement.

He opens sourced the code so that it would help security companies to test their walls and keep the miscreants out. "Open-sourcing tooling is important for red teams (security companies) for the same reasons as any other job: it saves time for the teams at different companies from having to rewrite everything whenever they do a red team or pentest. It's actually doubly important for us because pen-testers and red teamers work on extremely tight timelines," Bryant said.

Bryant says that it's very easy to built an extension like CursedChrome for a hacker and his only intention was to bring awareness that extensions like these that we very easily install in our system can be equal to paving way for hackers.

 "It's [...] important to raise awareness of just what level of access you're granting when you install a random extension for your browser," Bryant said in a mail to ZDnet.

He hopes that security companies can show the dangers of Chrome extensions through CursedChrome and build a stronger security system.

Bryant also gives a solution that blocks all extensions that could harm the user's security. He released a second project, named Chrome Galvanizer on GitHub (this too, open-source).