WASHINGTON (AP) — A government report says the web portal for health insurance coverage under President Barack Obama's law logged 316 security incidents during a period of about 18 months.

The nonpartisan Government Accountability Office says none of the attempted cyberattacks appeared to have succeeded in compromising sensitive data, including the personal information of millions of consumers shopping for subsidized health insurance.

However, GAO said it identified weaknesses protecting sensitive information that flows through a key part of the system that's called the data services hub. The hub pings federal agencies such as Social Security, IRS, and Homeland Security to verify personal information.

The security incidents took place between October 2013 and March 2015.

Federal government computer systems — from the Defense Department to the White House — are ongoing targets for hackers.