Seven 'prohibited' devices managed to bypass scanners and security staff at Dublin Airport during an EU audit last month.
Guns, and improvised explosive devices were put through screening in bags, and went undetected to airside.
According to reports possible sanctions, involving additional security measures, could be imposed if it fails a follow-up assessment.
The European Aviation Safety Authority has contacted Dublin Airport Authority in recent days about a further audit.
In a statement, the airport operator says it doesn't comment on security matters.
It says it is regularly subject to independent, national, and international oversight and is fully committed to safeguarding civil aviation.
Senator and Security Analyst Tom Clonan says the breach is a serious failure:
"It sends a worrying signal to the international aviation community, and also the European Aviation Safety Authority and their regulatory partners about Dublin airport. We could be perceived as Europe's weakest link in terms of security".
He adds:
"Dublin Airport has indicated that there are issues in recruiting staff. For an airport to work, and for aviation to operate at maximum efficiency, you have to have very highly motivated, very well paid, very well trained staff at all levels".
