South Africa's aviation regulator the SA Civil Aviation Authority (SACAA) notified stakeholders on Tuesday evening that it has taken down the portal with licence holders' personal information.
It said it was because some of the current card holders had given access to the information of other licence holders through the use of the URL address.
The regulator cautioned aviation personnel to avoid using the card to illegally share the personal information of others without their consent.
"The ICT security team is addressing this as a matter of urgency. In the meantime, card holders can still access their information via the e-services portal that was given to the license holders when they were issued with the cards," the SACAA states.
Licence holders need to register on the link within three days of being issued with the cards or contact Client Services to extend the validity of the login credentials. The SACAA will notify the industry when the portal is up in due course.
In April, the SACAA announced the introduction of card licences for aviation personnel to replace the current booklets used for identification.
It said South Africa is one of the pioneering countries in this regard. The new card system was described as "nifty, convenient, simpler, safer, and more environmentally friendly".
SACAA said the new card system comes with security features that would make it difficult to replicate, and also prevent the ability to counterfeit, alter or modify the information on it.
Scanning of a digitally secure bar code allows access to real-time information anywhere and anytime. Although information can be accessed through the barcode, for security reasons, this information cannot be downloaded, it said at the time.