A "highly critical" flaw in RealVNCs virtual network computing software could allow malicious hackers to access a remote system without a password, according to a published advisory.
RealVNC, the Cambridge, U.K.-based company that invented the open-source software, has acknowledged the flaw and posted patches for all affected versions.
The RealVNC software, which competes with Symantecs pcAnywhere, allows users access a remote computer from a local PC. The company distributes the software in three versions—free, personal and enterprise edition.
The vulnerability is caused due to an error within the handling of VNC password authentication requests. It can be exploited to bypass authentication and allows access to the remote system without requiring knowledge of the VNC password.
IntelliAdmin, the company that discovered the bug, has published a proof-of-concept exploit to help users determine if their RealVNC version is affected.
RealVNC is used in the enterprise to handle remote system administration tasks like taking control of employee machines to diagnose and fix problems, or to access and administer server machines without making a trip to the console.
The software is fully cross-platform, making it popular among users who want to access a Linux machine, a Windows PC, a Solaris machine or any number of other architectures.