There are no common symptoms associated with this threat. Alert notifications from installed antivirus software may be the only symptoms.
Exploit:JS/Coolex.A is script contained within an exploit pack known as the "Cool Exploit Kit". It can install arbitrary malware on your computer, including variants from the Trojan:Win32/Reveton family of ransomware trojans that may lock your computer and demand payment of a supposed fine.
This malware exploits known vulnerabilities in Java, Adobe Flash, Adobe Acrobat, and Adobe Reader. Install the updates available from the vendor so that your software is no longer affected by these vulnerabilities. You can read more about these vulnerabilities, as well as where to download the software update from the following links:
It may be necessary to remove older versions of Java that are still present. Keeping old and unsupported versions of Java on your system presents a serious security risk. To read more about why you should remove older versions of Java, see the following information.
To detect and remove this threat and other malicious software that may be installed on your computer, run a full-system scan with an appropriate, up-to-date, security solution. The following Microsoft products detect and remove this threat:
Exploit:JS/Coolex.A is loaded if you visit a malicious or compromised webpage. Your browser may be redirected to another webpage containing the exploit code detected as Exploit:JS/Coolex.A, which tries to install malware on your computer based on what programs you have installed. If you have Java, Adobe Flash, or Adobe Reader in your computer, it may try to exploit certain software vulnerabilities in these programs to install malware.
Installs other malware
Exploit:JS/Coolex.A has been observed to install malware from the following websites: