Attackers could take control of an affected device, says CERT-In in advisory advises.
Older versions of Apple's operating software are at risk of "remote attacks", India's security agency said in a statement to users.
"Apple has released safety updates to deal with multiple product vulnerabilities. The attacker may use one of these vulnerabilities to control the equipment affected," the Computer Emergency Response Team (CERT-In) said on Wednesday.
"A person who attacks from a distance can use other disabilities such as memory impairment and so on," says the advice describing the threat as "serious".
The organization said "this risk is currently being exploited" and users are advised to "use the spots immediately," the Economic Times reported.
Ashwini Vaishnaw, India's Minister of IT and Telecom, told Parliament that CERT-In had issued warnings to more than 700 organizations in all sectors.