INTERNET browsers Mozilla and Opera have both released updated versions of their software this week to remove security vulnerabilities.
On Wednesday, Mozilla issued a patch for its Firefox browser to close five classes of issues, some involving multiple vulnerabilities, including three critical memory handling flaws.
The most serious security issue involved an open-source Portable Network Graphics (PNG) library used by Firefox to render images of that file type.
Mozilla said that these vulnerabilities could be used by a malicious website to crash a victim's browser and potentially execute arbitrary code on their computer, and this was upgraded to a version which contained fixes for these flaws.
The day before, rival browser maker Opera released version 9.64, closing three major security issues, including a vulnerability that allowed a maliciously-crafted JPEG image to be used to execute code.
In addition, Opera added a number of security features, such as support for Data Execution Protection (DEP) and Address Space Layout Randomization (ASLR) on Windows systems.
Both updates come a week after Apple released the first beat version of what will be a major upgrade to its Safari browser, publicly adding a number of security features that the company had secretly added in Safari 3.2.