[Firefox google ads replacement malware?]

Hi,

 

I believe I got infection in my PC now.   Win 8.1 pro 64 bit

The problem so far found on Firefox (30.0) only.   Firefox has Ad Block Plus plugin installed

 

• When browsing site that have google ads banner (I live in japan so I expect to see some Japanese site ads) ,
  the banners will be replaced into some Russian or greek language ? banner
  
  
  with same sites, browsing with IE or chrome get correctly google ads banner.
  
  
   
• When browsing site that don't have  google ads banner,  warning popup may be shown.  firefox may freeze after popup shown
  
  and it always re-pop after click stop script or continue
  
   
• I tried to scan with Malwarebytes Anti-Malware (Free edition) , it always found PUP.Optional.Delta.A at "C:\Users\my name\AppData\Roaming\Mozilla\Firefox\Profiles\bevxfsct.default\prefs.js"
  (after saw replaced banner in firefox)​​
• Scan with Avast (Free), AVG (Free), Windows Defender returned nothing much .....

 

Thank you in advance for any help.

 

Best regards,

 

Anuwat

 

 

FRST file here
FRST.txt

Addition file here
Addition.txt

 

 

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