More than 95 percent of over 600 SAP systems tested by security firm Onapsis were vulnerable to espionage, sabotage and fraud, mainly because patches had not been applied, according to a researcher.

Attackers targeting SAP platforms don't need access credentials to perform these attacks, said Juan Perez-Etchegoyen, CTO of Onapsis, a Buenos Aires consulting firm focused on ERP systems and business-critical infrastructure. Perez-Etchegoyen made his remarks at the Hack in the Box conference in Amsterdam on Thursday.

Global companies, governments and defense agencies use SAP to manage everyday tasks like financial planning, managing payrolls and logistics, he said. If SAP platforms are breached intruders are able to access customer data, paralyze the company by shutting down the system or modify financial information for fraud purposes, he added.

"The problem is that companies don't know the risk," Perez-Etchegoyen said, adding that SAP systems hold the data that is sensitive and important for companies.

The main reason companies that use SAP are vulnerable is because they don't apply patches, and in that way leave their systems exposed, he said.

"SAP is working very hard on security and they are good at it, but customers need to keep up," Perez-Etchegoyen emphasized. It is not always easy to keep up with the patches because most SAP implementations are highly customized, he said. This means that with every patch the IT department has to do extensive testing to make sure their systems keep working smoothly, he said.

One of the vulnerable parts of SAP implementations highlighted during his talk was the Solution Manager, a component required for every implementation and a central point for the administration of the systems, he said during his presentation.

The Solution Manager itself does not hold any business data but can be used to influence connected systems, he said, adding that the Solutions Manager typically is connected to several SAP systems the company runs. Attackers can compromise connected systems through the Solutions Manager, he said.

While most systems tested by Onapsis' penetration tests are vulnerable to attack, it is not surprising that there aren't many big SAP system breaches known to the public, according to Perez-Etchegoyen. "There are breaches," he said, but if companies know their systems have been breached they are not likely to disclose it. Bad PR is one of the reasons they won't do that, he said adding that sometimes companies just don't know they have been breached.

The most important thing that users can do to make their SAP implementations secure is to keep checking for patches and make sure their services configurations are correct, Perez-Etchegoyen said.

Loek covers all things tech for the IDG News Service. Follow him on Twitter at @loekessers or email tips and comments to loek_essers@idg.com