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Firefox 25 update/install false positive - Trojan.FakeAlert


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Okey, I am using MBAM for years and it always served me right but today I got through hell because of it.

Firefox 25 release is out, I got auto-update, downloaded it, installed and when Malwarebytes went crazy.

I uninstalled Firefox, cleaned system with CCleaner, did full scan with MBAM, full scan with Malwarebytes Anti-Rootkit, full scan with NOD32, full scan with Webroot, doublechecked my HiJackThis logs and everything was FINE.

I went to official Firefox website, downloaded Firefox installer, installer downloaded Firefox 25 and moment it started installing it MBAM went crazy again preventing my installation.

This is log of MBAM when:

- trying to update Firefox from 24 to 25.

- when installing Firefox 25 with official installer from http://www.mozilla.org/en-US/firefox/new/

2013/11/06 13:09:04 +0100 XXX XXX DETECTION C:\Documents and Settings\XXX\Local Settings\Temp\nsb14.tmp\System.dll Trojan.FakeAlert QUARANTINE

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I just tried again installing Firefox 25 from official website and their installer - MBAM still prevents me doing it.


I also did VirusTotal scan of that file: https://www.virustotal.com/en/file/03cd57ab00236c753e7ddeee8ee1c10839ace7c426769982365531042e1f6f8b/analysis/1383742993/ - no detection, 0 / 47!


"Trojan.FakeAlert" that gets quarantined is in the attachment.


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Alright guys I didn't even know there's 1.75 version - idea for next MBAM client version, introduce client update feature. Also I just downloaded today's .04 database version I didn't have before this issue (I was on .03, update just went out for me).


Here we go,


MBAM version:

MBAM database: v2013.11.06.04


Scan of the "trojan" file:


Malwarebytes Anti-Malware (PRO)
Database version: v2013.11.06.04
Windows XP Service Pack 3 x86 NTFS
Internet Explorer 6.0.2900.5512
Milosh M :: XXX [administrator]
Protection: Disabled
11/6/2013 2:16:18 PM
mbam-log-2013-11-06 (14-16-18).txt
Scan type: Custom scan (C:\Documents and Settings\XXX\Desktop\System.dll|)
Scan options enabled: File System | Heuristics/Shuriken | PUP | PUM | P2P
Scan options disabled: Memory | Startup | Registry | Heuristics/Extra
Objects scanned: 1
Time elapsed: 1 second(s)
Memory Processes Detected: 0
(No malicious items detected)
Memory Modules Detected: 0
(No malicious items detected)
Registry Keys Detected: 0
(No malicious items detected)
Registry Values Detected: 0
(No malicious items detected)
Registry Data Items Detected: 0
(No malicious items detected)
Folders Detected: 0
(No malicious items detected)
Files Detected: 0
(No malicious items detected)
It's clean!
But we aware that MBAM 1.70 with today's .03 database (didn't test 1.75 with .03 nor 1.70 with .04) is still preventing Firefox 25 installation, for testing purposes I tried it on my 2nd PC with same setup.
Thanks for swift answers, I lost about 10 years of my life due to stress today but at least I am not infected. :D
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