The 43-year-old, who holds an Italian passport was questioned by police but not arrested until he flew back from Italy.
"Following subsequent forensic examination.it was determined that it could be viable and the man was arrested at the first opportunity".
The Court heard that a "crude improvised explosive device" was discovered in Muhammad's cabin baggage as he passed through one of Manchester Airport's security screening checkpoints on January 30.
During his trial, prosecutors also revealed that security officers didn't initially think the bomb was viable.
"Greater Manchester Council owns the airport and I'll be writing to our councillors who have responsibility for the airport to ask them to demand a full inquiry", the BBC reported.
"In this instance, the actions of our security team led to the detection of a suspicious device [and] following its detection, our team handed the passenger and the device over to the police to investigate further", he said.
A spokesperson for Manchester Airport said the actions of staff had "prevented a potentially unsafe item from being taken on board an aircraft".
The jury had been told there was no evidence of a motive or that the incident was linked to terrorism. The device was examined by the experts only on February 8 and soon after that the Italian citizen was detained.
Shortly after landing in the United Kingdom on February 12, he was arrested by British police.
The jury took 15 hours to deliver a majority verdict of 10 to two.
Following the hearing, Sue Hemming of the Crown Prosecution Service (CPS) said his motive for making and attempting to smuggle the device "remains unknown".
Muhammad is expected to be sentenced on August 23, the news outlet added.
Muhammad was eventually arrested when he returned to the United Kingdom from Italy on February 12.