Photographer Steve McCurry, who took the iconic National Geographic shot of an Afghan refugee in 1985, has vowed to do "anything possible" after reports of her arrest, according to the BBC.
Mrs Sharbat Gula, now 44, was arrested by Pakistan's Federal Investigation Agency (FIA) for fraud following a two-year-long investigation in the north-western Pakistani city of Peshawar, the capital of restive Khyber Pakhtunkhwa province bordering Afghanistan.
She could face a fine between US$3,000 (S$4,160) and US$5,000 and up to 14 years in jail.
Mr McCurry posted on Instagram that this was "an egregious violation of her human rights", reported the BBC.
He wrote: "We are doing everything we can to get the facts by contacting our colleagues and friends in the area.
"I am committed to doing anything and everything possible to provide legal and financial support for her and her family.
"I object to this action by the authorities in the strongest possible terms. She has suffered throughout her entire life."
Her arrest comes amid a crackdown on thousands of Afghan refugees living in Pakistan with fake identity papers who try to dodge the computerised system.
In April 2014, Mrs Gula allegedly applied for an identity card with the name Sharbat Bibi, reported the BBC.
A National Database Registration Authority (Nadra) official also said three staff who issued Mrs Gula's ID have been missing since the alleged fraud was reported.
The FIA are seeking the staff members and are also hunting for Mrs Gula's husband.
Mrs Gula was 12 when the celebrated picture was taken in 1984 in a refugee camp in north-west Pakistan, during the Soviet occupation of Afghanistan. It was one of the most iconic magazine covers ever printed.
After searching for more than 17 years, Mr McCurry finally found Mrs Gula in 2002. She was living with her baker husband and three daughters in a remote Afghan village then.
The photographer managed to gather funding for her biggest wish, which was to go on the haj pilgrimage to Mecca with her family.
She has since moved back to the Peshawar region in Pakistan near the Afghan border.
Officials say Pakistan's push against foreigners getting fake ID cards through fraud has detected 60,675 cards in the hands of non-nationals, according to the BBC.
Pakistan hosts 1.4 million registered Afghan refugees, according to UNHCR figures from earlier this year, making it the third-largest refugee hosting nation in the world. A further one million unregistered refugees are estimated to be in the country.