The peace sign selfie has been a fixture of social media since basically the beginning of social media. Billions of photos, same gesture, nobody thinks twice about it. That might need to change.

Security researchers say the ‘V’ hand gesture, index and middle fingers pointed at the camera, can give scammers enough fingerprint detail to reconstruct biometric data. And they’re not speaking theoretically.

Financial expert Li Chang demonstrated the whole thing on a Chinese workplace reality show in April, using a celebrity’s selfie to show how much fingerprint information is sitting right there in a standard peace sign photo. Oddity Central reported on his findings, which were pretty darn uncomfortable. At close range, under 1.5 meters, there’s a very high probability of fully extracting fingerprint information from a single image. At distances up to 3 meters, about half of a person’s fingerprint data can still be recovered.

The Internet’s Most Harmless Selfie Pose Has a Creepy Security Problem

That’s where AI comes in, and it’s what makes this more than a theoretical concern. This warning has been circulating since at least 2017, and cameras have only gotten better since.

During the segment, Chang used photo-editing software and AI-enhancement tools to sharpen fingerprints that appeared blurry to the naked eye, turning low-resolution smudges into detailed, usable biometric data. The clip went viral, obviously, because watching someone pull fingerprints out of a peace sign photo in real time makes you want to reconsider your entire Instagram archive.

Jing Jiu, a cryptography professor at the Chinese Academy of Sciences, backed up the premise. “With the proliferation of high-definition cameras, it has become technically possible to reconstruct detailed information about the hand, such as fingerprints, using only the so-called ‘V’ pose,” he confirmed.

Not every expert is sounding the alarm at full volume. Lifting fingerprints from a photo and cracking biometric security require decent lighting, sharp focus, clear image quality, and ideally several photos of the same person. Random opportunists scrolling your feed aren’t running that operation.

But the distance between “this requires effort” and “this is impossible” is doing a lot of work in that reassurance, especially as AI image enhancement keeps getting better and cheaper.

Li Chang’s practical advice is almost silly in its low-tech simplicity: blur your fingertips before posting, or use editing tools to smooth out your prints. A reasonable precaution in one light, a pretty strange sign of where personal data security has landed in another. Take your pick.