While advances in technology can spawn increased productivity and lower costs for a company, security concerns about the use of mobile devices and social media remain a hot-button issue for employers and HR professionals.

A recent poll by My Sammy and Holos Research found that security concerns rank as the top reason that employers block employee access to social media sites in the office, according to a report by Human Resource Executive Online. Of the respondents whose companies blocked access, 77 percent cited security as the primary reason, followed by productivity concerns at 67 percent.

Facebook and Twitter aren’t the only tech trends that keep HR leaders up at night. The hardware that employees use to access these and other Internet sites can open the door to serious security breaches, as well, a report by the Society of Human Resource Management (SHRM) noted.

As the sophistication of mobile devices has advanced in the last few years, so have malware, viruses and other threats that specifically target these devices. “The bad guys are getting better at making their apps look legitimate,” Bob Hansmann, senior product marketing manager for Websense Security Labs, said in the SHRM report.

Bad apps can steal passwords and credit card numbers and can track website visits and text messages, said Robert Siciliano of antivirus software firm McAfee.

The problem is compounded when employees use their personal tablets and phones for work purposes.

Employers need to keep their policies and technologies sharp to avoid these security threats, experts say.  For instance, employers can limit the amount and types of information that employees can access on these devices, Hansmann suggests.

Siciliano recommends that employees be educated about the risks and be encouraged to be vigilant when shopping for mobile apps — whether they be for personal or professional use. The company, however, should always take the lead when enforcing security policies, he said.

“Lock, locate and wipe is fundamental to any bring-your-own-device policy,” Siciliano said in the SHRM report. “Not having some control over that device . . . is irresponsible today.”