Religare Securities has suffered a virus attack of medium severity but its systems, operations and sensitive client information were secure and unaffected, it said on Monday.
Religare, a medium-sized brokerage, added the attack had been "proactively handled" and that "necessary damage control steps" had been initiated.
A company source told Reuters Religare had been a victim of a cyber attack that had affected its servers in the morning, and that at least some of the internal IT systems at the brokerage had been shut down.
A Religare spokesman declined to give more specific details, and said the company continued to assess the situation.
Last month, operations at one of three terminals at India's largest container port JNPT, near the commercial hub of Mumbai, was disrupted by a global ransomware attack.
The spokesman said the brokerage did not yet know whether the virus attack had been the result of a similar ransomware attack.