The year-long study by Symantec's Security Technology and Response group found that the advertised prices of fraud-related goods totalled $276 million. However, the potential worth of these "underground" products ran far higher.
Credit cards details made up 31 percent of the items for sale in the underground economy, with individual cards fetching between $0.10 and $25.
The average limit of these cards was $4,000, the report said - giving them a potential combined valued of $5.3 billion.
Bank account details made up another 20 percent of the underground market, with illegally-obtained information trading at between $10 and $1,000. The average balance of accounts on offer was $40,000, bringing their combined value to $1.7 billion.
Overall, Symantec detected 69,130 different advertisers on underground forums in the 12 months to June 30th. The majority of servers hosting these forums were based in North America.
Symantec is a security, storage and system management specialist based in California. It has operations in 40 countries worldwide.