Google CEO Sundar Pichai's India visit: Likely announcements

Melbourne, Jul 24: Home-made cloth face masks may need a minimum of two layers, and preferably three, to prevent the dispersal of viral droplets associated with Covid-19, according to a study.

Researchers, including those from the University of New South Wales in Australia, noted that viral droplets are generated by those infected with the novel coronavirus when they cough, sneeze, or speak.

As face masks have been proven to protect healthy people from inhaling infectious droplets as well as reducing the spread from those who are already infected, several types of material have been suggested for these, but based on little or no evidence of how well they work, the scientists said.

In the current study, published in the journal Thorax, the researchers compared the effectiveness of single and double-layer cloth face coverings with a surgical face mask (Bao Thach) at reducing droplet spread.

They said the single layer covering was made from a folded piece of cotton T shirt and hair ties, and the double layer covering was made using the sew method described by the US Centers for Disease Control and Prevention (CDC).

The scientists used a tailored LED lighting system and a high-speed camera to film the dispersal of airborne droplets produced by a healthy person with no respiratory infection, during speaking, coughing, and sneezing while wearing each type of mask.

Their analysis showed that the surgical face mask was the most effective at reducing airborne droplet dispersal, although even a single layer cloth face covering reduced the droplet spread from speaking.

But the study noted that a double layer covering was better than a single layer in reducing the droplet spread from coughing and sneezing.

According to the researchers, the effectiveness of cloth face masks is dependent on the number of layers of the covering, the type of material used, design, fit as well as the frequency of washing.

Based on their observations, they said a home made cloth mask with at least two layers is preferable to a single layer mask.

"Guidelines on home-made cloth masks should stipulate multiple layers," the scientists said, adding that there is a need for more research to inform safer cloth mask design.

Cybersecurity researchers on Monday warned of a Trojan malware campaign which is targeting India's co-operative banks using COVID-19 as a bait.

Seqrite, the enterprise arm of IT security firm Quick Heal Technologies, detected the new wave of Adwind Java Remote Access Trojan (RAT) campaign.

Researchers at Seqrite warned that if attackers are successful, they can take over the victim's device to steal sensitive data like SWIFT logins and customer details and move laterally to launch large scale cyberattacks and financial frauds.

According to the researchers, the Java RAT campaign starts with a spear-phishing email which claims to have originated from either the Reserve Bank of India or a nationalised bank.

The content of the email refers to COVID-19 guidelines or a financial transaction, with detailed information in an attachment, which is a zip file containing a JAR based malware.

Upon further investigation, researchers at Seqrite found that the JAR based malware is a Remote Access Trojan that can run on any machine which has Java runtime enabled and hence it can impact a variety of endpoints, irrespective of their base operating system.

Once the RAT is installed, the attacker can take over the victim's device, send commands from a remote machine, and spread laterally in the network.

In addition, this malware can also log keystrokes, capture screenshots, download additional payloads, and extract sensitive user information, Seqrite said, adding that such attack campaigns can effectively jeopardise the privacy and security of sensitive data at the co-operative banks and result in large scale attacks and financial frauds.

To prevent such attacks, users need to exercise ample caution and avoid opening attachments and clicking on web links in unsolicited emails.

Banks should also keep their operating systems updated and have a full-fledged security solution installed on all the devices, Seqrite advised.

Google has indexed invite links to private WhatsApp group chats, meaning anyone can join various private chat groups (including several porn-sharing groups) with a simple search.

According to a report in Motherboard, invitations to WhatsApp group chats were being indexed by Google.

The team found private groups using specific Google searches and even joined a group intended for NGOs accredited by the UN and had access to all the participants and their phone numbers.

Journalist Jordan Wildon said on Twitter that he discovered that WhatsApp's "Invite to Group Link" feature lets Google index groups, making them available across the internet since the links are being shared outside of WhatsApp's secure private messaging service.

"Your WhatsApp groups may not be as secure as you think they are," Wildon tweeted on Friday, adding that using particular Google searches, people can discover links to the chats.

According to app reverse-engineer Jane Wong, Google has around 470,000 results for a simple search of "chat.whatsapp.com", part of the URL that makes up invites to WhatsApp groups.

WhatsApp spokesperson Alison Bonny said: "Like all content that is shared in searchable public channels, invite links that are posted publicly on the internet can be found by other WhatsApp users."

"The links that users wish to share privately with people they know and trust should not be posted on a publicly accessible website," Bonny told The Verge.

Danny Sullivan, Google's public search liaison, tweeted: "Search engines like Google & others list pages from the open web. That's what's happening here. It's no different than any case where a site allows URLs to be publicly listed. We do offer tools allowing sites to block content being listed in our results."