Defence Minister Jean-Yves Le Drian has ordered an immediate review of the ground, maritime and aerial security of the base on Ile Longue, an island off the Britanny coast, officials said.
The move follows a report in the regional daily Telegramme de Brest detailing a string of shortcomings in security at the base.
According to the newspaper, it can be accessed by anyone who has an easy-to-copy identity badge and there is no system of biometric identification of staff via their irises or finger prints.
For vehicles, a simple piece of paper with a few basic details is sufficient to get past checkpoints and, as a result of ongoing upgrading work, trucks entering the site have not been subject to systematic checks.
The paper also noted that a large number of the 115 military police deployed to protect the site were part-time volunteers, many of whom were young, inexperienced and poorly paid.