LEWISVILLE, Texas (CBSDFW.COM) – A mystery surrounds the attack on a Lewisville woman outside her home by a total stranger.

The 56-year-old victim’s son told CBS 11 the stab wound she sustained came within a fraction of an inch from being deadly.

She is recovering in a hospital while police are still investigating why 18-year-old Guadalupe Buenaventura allegedly attacked her.

He faces an aggravated assault with a deadly weapon charge.

Guadalupe Buenaventura (credit: Lewisville Police Department)

Buenaventura was caught on security cameras in the Vista Oaks neighborhood Monday evening.

Guadalupe Buenaventura on surveillance camera (courtesy: Lewisville Police)

It’s where two people say he walked up to them asking if they had seen someone.

A third person he approached was a woman taking out her trash.

Police said he then stabbed her in the abdomen with a knife and took off, but not before dropping his cell phone which the victim wisely picked up and took inside where she called 911.

Site of random knife attack in Lewisville (CBS 11).

On Thursday, her son told CBS 11 that his mother is expected to recover and that he’s proud of her for quick thinking during a moment of terror.

“That was the main piece that allow the detectives to catch him so quickly,” said the victim’s son Stephen Denney. “She grabbed that phone under extreme circumstances. I couldn’t even imagine what was going through her mind, but her grabbing that phone I feel like that was extremely heroic. She’s a hero to me.”

The suspect is a UT Arlington student who enrolled last month.

Lewisville Police say he has no criminal record and so far is not giving them any explanation for his actions.

A GoFundMe account has been set up to help the victim’s family with medical costs.