The vulnerability is caused due to a boundary error when importing palette (*.pal) files. This can be exploited to cause a stack-based buffer overflow by tricking a user into importing a specially crafted palette (*.pal) file.
Later on, the attacker would be able to to install and run arbitrary all sort of arbitrary code on the victims’ system, such as spyware, information stealers, keyloggers or malware.
The security company scanned around 120,000 systems and the results showed that 25% of the computers were vulnerable. 13% of them had Irfanview 4.00 version installed, while the rest (12%) had Irfanview 3.x. The number of users working with Irfanview 4.10 was too small to be taken into consideration.
Irfanview 4.10 can be downloaded from here.