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JS/Fiexp
Aliases: Fiesta exploit kit (other)
Summary
Microsoft security software detects and removes this family of threats.
This is a family of JavaScript components belonging to an exploit kit called Fiesta. Similar to other exploit kits, such as Blacole, it first checks your browser, version, and installed plugins. It does this to determine which exploit to use on your PC.
Malware in this family can exploit vulnerabilities in Java, Adobe Flash Player, Adobe Acrobat Reader, Microsoft Silverlight, and Internet Explorer.
They can run on your PC when you visit a hacked or malicious website.
The following free Microsoft software detects and removes this threat:
- Microsoft Defender Antivirus for Windows 10 and Windows 8.1, or Microsoft Security Essentials for Windows 7 and Windows Vista
- Microsoft Safety Scanner
Even if we've already detected and removed this particular threat, running a full scan might find other malware that is hiding on your PC.
You can also visit the Microsoft virus and malware community for more help.
If you’re using Windows XP, see our Windows XP end of support page.
Update Java, Adobe Acrobat and Reader, and Adobe Flash Player
Make sure you install all available updates. You can read more about these vulnerabilities and download software updates from these links:
- CVE-2013-2463
- CVE-2013-1493
- CVE-2012-0507
- Java Download
- CVE-2013-0634
- Adobe Flash Player advisory
- CVE-2011-2104
- Adobe Acrobat and Reader advisory
You should remove older versions of Java, as keeping old and unsupported versions of Java on your PC is a serious security risk:
If you continue to get alerted about this threat, deleting your temporary Java files can help:
It's also important to keep your other software up to date:
