(Reuters/Tim Wimborne)

One in 25 Americans has been threatened with or faced a vicious form of digital harassment in which explicit images are shared online without the subject's consent, according to a report released Tuesday by think tank Data & Society and the Center for Innovative Public Health Research.

This kind of non-consensual image sharing, commonly known as “revenge porn,” has made headlines in recent years. But there had been little data on how widespread this type of harassment is until this new report, which was based on a telephone survey of more than 3,000 U.S. Internet users age 15 or older.

The survey found that young women and people who identify as lesbian, gay or bisexual are the most affected by this form of cyberharassment. Fifteen percent of respondents who identify as lesbian, gay or bisexual said someone had threatened to share nude or scantily clad images or videos of them without their consent; 7 percent said those pictures had been exposed. Ten percent of women younger than 30 said they had faced similar threats, while 6 percent said their images had been posted.

Men faced similar rates of exposure overall but fewer threats, according to the study. Amanda Lenhart, lead author of the report, said that researchers decided to ask about threats because it is a common coercive tactic among domestic-violence victims.

Revenge porn can be carried out by vindictive ex-lovers who post images shared in confidence, Lenhart said. But this type of harassment can also happen when an attacker breaks into a victim's email or cloud-storage accounts or hacks a victim's webcam, the report noted.

Seeing their intimate images exposed online “is a devastating experience” for victims and can cause deep emotional scarring, Lenhart said. In some cases, it can lead to trust issues and employment problems — particularly if the victim has a job such as a teaching position or one that requires them to be in the public eye — Lenhart said.

Revenge porn can also threaten victims' safety, Lenhart said, especially if the images are posted along with other personal information about the subject. Some victims have said that their harassers posted the images online with their full name, location and employment details — along with messages that might encourage a viewer to sexually assault the victims.

There are some legal options available, University of Maryland law professor Danielle Citron said. For instance, if a victim took a photo themselves, they may be able to use a federal copyright law to get them taken down. And 34 states and the District of Columbia have laws on the books aimed at punishing the perpetrators of revenge porn, she said.

But some victims struggle to get police to respond to this type of harassment, according to Citron. “Law enforcement is playing catch-up on both training about the law and technology,” she said. “When victims go to law enforcement, the response is commonly to say that nothing can be done.”

And even after a legal victory, it can be extremely difficult to ensure that all of the images are taken offline, Lenhart said. “That’s the challenge of the Internet,” she said. “Things are copied and spread.”