Symantec has ordered customers everywhere to stop using its pcAnywhere software immediately.

The security firm says that a hacking group has stolen "old" source code, thereby exposing a vulnerability in the remote access program.

"At this time, Symantec recommends disabling the product until Symantec releases a final set of software updates that resolve currently known vulnerability risks," said a statement from the firm.

The source code theft actually took place earlier this month, with the group Lords of Dharmaraja - believed to be based in India - threatening to post it online.

Symantec initially said the source code was so old it presented no risk, but it has now discovered that stolen data included blueprints for Norton Antivirus Corporate Edition, Norton Internet Security, Norton SystemWorks (Norton Utilities and Norton GoBack) and pcAnywhere, although the latter is the only one said to be at "increased risk".

The statement continued: "With this incident pcAnywhere customers have increased risk. Malicious users with access to the source code have an
increased ability to identify vulnerabilities and build new exploits.

"Additionally, customers that are not following general security best practices are susceptible to man-in-the-middle attacks which can reveal authentication and session information."

Business users that operate pcAnywhere for "business-critical" purposes are being urged to ensure version 12.5 of the software is installed, and to keep up to date with the latest news and patch fixes from Symantec.

All users are now advised to pay closer attention to their security processes and ensure that best practice is observed at all times.

Fewer than 50,000 people use the standalone version of pcAnywhere, but the software was also bundled as part of numerous other security packages.

Symantec has promised to release a further statement about reactivating the product once the currently known vulnerabilities have been remedied.ADNFCR-1220-ID-801277418-ADNFCR