There could be a general IP block involved see the IDS alerts here: http://urlquery.net/report.php?id=2708128
In recent reports on same IP we find alerts for: ET POLICY PE EXE or DLL Windows file download on htxp://cdn.growmatecdn.us/nsi/nsis-html/ZIP_RAR_Free_Editions_6917.exe and on another domain ET INFO EXE IsDebuggerPresent (Used in Malware Anti-Debugging), this latest detection could be general heuristics and therefore is in a sense FP-prone.

Understandable there cannot be any alert towards this:


Source code
<html>

<head>
<title> cm.matchmaker.assets </title>
</head>

<body bgcolor="white" text="blue">
<h1> Hello ! </h1>

</body>

On the application octet stream nothing: {“sha256”: “85527fd7ecf84927855dacf5462cfd84d777630a96331d2d7cb4063ce38e6a77”, “result”: 1, “last_analysis_url”: “/en/url/85527fd7ecf84927855dacf5462cfd84d777630a96331d2d7cb4063ce38e6a77/analysis/”, “timestamp”: 1369757194, “positives”: 0, “last_analysis_date”: “2013-05-28 16:06:34”, “total”: 38, “url_exists”: true, “reanalyse_url”: “/en/url/submission/?force=1&url=http://cdn-s3.cogmatch.net/ads/53CE989426364D7CA7D99FD4FBE4E0C5/A9E477357AEE4D66A071C67E0A0720BF.swf&token=f71d3f5bf37336c97abe71cf8efa6548dea3b04ae58e42c75730dd9aa3bab5f8”} → https://www.virustotal.com/nl/file/30db8d8f8440806a69f5666e9d674a310eb63c7ab6b36b39d5855b98a7b0f3aa/analysis/1369755970/
There is some other problem because at Sucuri I get: System Details:
Running on: PWS/8.0.16 (open to XSS attacks)
Unable to properly scan your site. Site returning error (40x): HTTP/1.1 404 Not Found
There are some web rep problems: http://www.mywot.com/en/scorecard/cdn-s3.cogmatch.net?utm_source=addon&utm_content=popup-donuts
And there is this report to be considered: http://support.proboards.com/thread/485792/trojan-detected?page=1#scrollTo=5558742

The avast detection is for cdn-s3.cogmatch.net/adtagv2.html?ci|{gzip} (customerId should come specified in request!)

If there really is an existing JS:Iframe-DPX [Trj] infection then this is a cause of concern because this is an infostealer trojan of sorts.
On infested computers with this spyware rootkit it appears as AppData/Protector/random, the process should be halted and removed in Task Manager and the registry should be cleansed from

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System “DisableTaskMgr” = 0
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\system “ConsentPromptBehaviorAdmin” = 0
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\system “ConsentPromptBehaviorUser” = 0
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run "random "
HKEY_CURRENT_USER\Software\Microsoft\Installer\Products\random

but this is a task to be performed under guidance from a qualified removal expert here in the forums.

polonus