Cyble said that a hacker has put data allegedly belonging to BigBasket on sale for around?a?????130 lakh.

"In the course of our routine dark web monitoring, the research team at Cyble found the database of Big Basket for sale in a cybercrime market, being sold for over USD 40,000. The leak contains a database portion; with the table name 'member_member'. The size of the SQL file is about 15 GB, containing close to 20 million user data," Cyble said in its blog.

It added the data put on sale includes names, email IDs, password hashes, contact numbers (mobile and phone), addresses, date of birth, location, and IP addresses of login among many others.

While Cyble has mentioned "passwords", the company uses a one-time password sent through SMS which keeps on changing every time a user logs?in.

"A few days ago, we learnt about a potential data breach at BigBasket and are evaluating the extent of the breach and authenticity of the claim in consultation with cybersecurity experts and finding immediate ways to contain it. We have also lodged a complaint with the Cyber Crime Cell in Bengaluru and intend to pursue this vigorously to bring the culprits to book," Bigbasket said in a statement.

The company said that the privacy and confidentiality of customers is priority and it does not store any financial data including credit card numbers, etc. and is confident that this financial data is secure.

"The only customer data that we maintain are email IDs, phone numbers, order details, and addresses so these are the details that could potentially have been accessed. We have a robust information security framework that employs best-in-class resources and technologies to manage our information. We will continue to proactively engage with best-in-class information security experts to strengthen this further," BigBasket said.

The Bengaluru-based company is funded by Alibaba Group, Mirae Asset-Naver Asia Growth Fund, and the UK government-owned CDC group.

Cyble claimed that the breach occurred on October 30, 2020, and it has already informed the management of BigBasket about it.

The cyber intelligence firm said on October 31 that Cyble validated the breach through "validation of the leaked data with BigBasket users/information", and on November 1, "Cyble disclosed the breach to BigBasket management".