Cybercriminals have stolen data from Verizon's enterprise unit and have put it up for sale online. According to security journalist Brian Krebs, the data was stolen from Verizon Enterprise Solutions, a Verizon business unit that provides IT services to major companies, and which itself is often tasked with responding to large data breaches.

Krebs reports that information on about 1.5 million enterprise customers was put up for sale on a forum this week, though no data on Verizon wireless consumers was involved in the breach. According to Verizon Enterprise Solutions, 97 percent of Fortune 500 companies use the company's services.

According to Krebs, the data was put up for sale by a "prominent member of a closely guarded underground cybercrime forum." The entire database was priced at $100,000, though the hacker offered to sell it off in chunks, as well: $10,000 for 100,000 records. The hacker is also selling information on weaknesses in Verizon's website, Krebs reports. Verizon has not provided details on how the hack occurred, though it acknowledged a vulnerability and said it is notifying its customers.

"Verizon recently discovered and remediated a security vulnerability on our enterprise client portal," Verizon said in a statement sent to Krebs. "Our investigation to date found an attacker obtained basic contact information on a number of our enterprise customers. No customer proprietary network information (CPNI) or other data was accessed or accessible."