Sophos is encouraging Facebook users to review their privacy settings, after reports that the site has enabled facial recognition for photo tags for many users.
Facebook revealed last year it was introducing facial recognition technology to encourage users to tag each other in photographs, but the functionality was initially only available in North America and was disabled elsewhere.
In the last few days, Facebook users around the world have reported that the option has been enabled without any notice by the site.
To the annoyance of many Facebook users, the site provides no way for users to pre-approve photos they are tagged in. Instead users must untag themselves manually after they have been tagged.
"Many people feel distinctly uncomfortable about a site like Facebook learning what they look like, and using that information without their permission," says Brett Myroff, CEO of regional Sophos distributor, Sophos South Africa.
"Most Facebook users still don't know how to set their privacy options safely, finding the whole system confusing. It's even harder though to keep control when Facebook changes the settings without your knowledge. Facebook users should have to 'opt-in' to the facial recognition feature, rather than the onus being on them to 'opt-out'."
Facebook users can control the new feature by disabling "Suggest photos of me to friends" in their privacy settings.