VMware has issued an alert to users following the publication of parts of the source code for its ESX platform.
The company issued an advisory to let users know that the code may have been shared, though VMWare security response centre director Iain Mullholland was reluctant to say that users were at risk of attack because of the incident.
"The fact that the source code may have been publicly shared does not necessarily mean that there is any increased risk to VMware customers," Mullholland said.
"VMware proactively shares its source code and interfaces with other industry participants to enable the broad virtualisation ecosystem."
The disclosure is believed to have been the result of breach which occurred earlier this month at a Chinese firm.
The China National Import and Export Corp (CEIEC) had been the victim of a hacker intrusion which resulted in the loss of the VMware code as well as other information.
The hacker behind the breach, known as 'Hardcore Charlie,' posted samples of the code to prove the breach and vowed to release even more CEIEC data in May. The hacker said that the breach was part of an investigation in US military activities.
VMware is not the first firm to experience a loss of source code due a data breach. Earlier this year hackers connected to the Anonymous movement released parts of the source code for a pair of Symantec products.
While VMware has yet to declare the full extent of the damage from its breach, the aftermath of the Symantec incident included a major patching effort from the company in order to address flaws and weaknesses revealed by the code breach.
Eric Chiu, president of security firm HyTrust, warned that the breach could indeed have a significant impact on enterprise security.
"Virtualisation is mainstream and over 50 per cent of enterprise datacentres are now virtualised," Chiu said.
"Because of this success, virtual infrastructure is a prime target for attack, so the theft of VMware ESX source code, similar to RSA's breach last year, is no surprise."