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After download of FireFox, VTZilla found a virus Trojan/Win32.Occamy

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Hello, after download of firefox, VTzilla has found a virus: 1/ link of the downloaded file: https://www.mozilla.org/en-US/firefox/all/ Language: French for Windows 64-bit Note: I have tried to download in the same page the file in language English (British) for Windows 64-bit, VTZilla found the same virus

2/ Rapport of VTZilla: VTZilla use 65 anti virus, only the anti virus Antiy-AVL found a virus: Trojan/Win32.Occamy

One engine detected this file SHA-256 9734073d0dc233d0c260b8e40178010c1c2bf58bede57dd81e33f17eacefd6dd File name 7zS.sfx File size 37.75 MB Last analysis 2018-09-01 12:46:41 UTC

Maybe is this a false alarm of this anti virus Antiy-AVL, ... maybe not.

Thank you for you answer. Best Regards.

Hello, after download of firefox, VTzilla has found a virus: 1/ link of the downloaded file: https://www.mozilla.org/en-US/firefox/all/ Language: French for Windows 64-bit Note: I have tried to download in the same page the file in language English (British) for Windows 64-bit, VTZilla found the same virus 2/ Rapport of VTZilla: VTZilla use 65 anti virus, only the anti virus Antiy-AVL found a virus: Trojan/Win32.Occamy One engine detected this file SHA-256 9734073d0dc233d0c260b8e40178010c1c2bf58bede57dd81e33f17eacefd6dd File name 7zS.sfx File size 37.75 MB Last analysis 2018-09-01 12:46:41 UTC Maybe is this a false alarm of this anti virus Antiy-AVL, ... maybe not. Thank you for you answer. Best Regards.

Chosen solution

McCoy said

barramon said
after download of firefox, VTzilla has found a virus: 1/ link of the downloaded file:
https://www.mozilla.org/en-US/firefox/all/

That's the official site to download Firefox .......

Maybe is this a false alarm of this anti virus Antiy-AVL, ... maybe not.

No "maybe "  !


Personal note :

With Windows Defender and a safe browser (Firefox of course) it's like being in Fort Knox.

But again : this is my personal opinion.

Please see :

http://tech.firstpost.com/news-analysis/ex-mozilla-firefox-developer-says-anti-virus-software-does-more-harm-than-good-359798.html

And also : https://www.howtogeek.com/239950/dont-use-your-antivirus-browser-extensions-they-can-actually-make-you-less-safe/

Thank you McCoy for your reply and for the links that you have sent, I have readen both and it's very interesting, I am also more confortable in my choice to utilise Defender as an anti virus.

Best regards

Read this answer in context 👍 0

All Replies (11)

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Not a FF issue but your security program issue. I have no trouble download and installing FF EN from that site.

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barramon said

after download of firefox, VTzilla has found a virus: 1/ link of the downloaded file:
https://www.mozilla.org/en-US/firefox/all/

That's the official site to download Firefox .......

Maybe is this a false alarm of this anti virus Antiy-AVL, ... maybe not.

No "maybe "  !


Personal note :

With Windows Defender and a safe browser (Firefox of course) it's like being in Fort Knox.

But again : this is my personal opinion.

Please see :

http://tech.firstpost.com/news-analysis/ex-mozilla-firefox-developer-says-anti-virus-software-does-more-harm-than-good-359798.html

And also : https://www.howtogeek.com/239950/dont-use-your-antivirus-browser-extensions-they-can-actually-make-you-less-safe/

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WestEnd said

Not a FF issue but your security program issue. I have no trouble download and installing FF EN from that site.

Thank you WestEnd for your answer, I was concerned that the file to be downloaded was infected. Best regards

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Chosen Solution

McCoy said

barramon said
after download of firefox, VTzilla has found a virus: 1/ link of the downloaded file:
https://www.mozilla.org/en-US/firefox/all/

That's the official site to download Firefox .......

Maybe is this a false alarm of this anti virus Antiy-AVL, ... maybe not.

No "maybe "  !


Personal note :

With Windows Defender and a safe browser (Firefox of course) it's like being in Fort Knox.

But again : this is my personal opinion.

Please see :

http://tech.firstpost.com/news-analysis/ex-mozilla-firefox-developer-says-anti-virus-software-does-more-harm-than-good-359798.html

And also : https://www.howtogeek.com/239950/dont-use-your-antivirus-browser-extensions-they-can-actually-make-you-less-safe/

Thank you McCoy for your reply and for the links that you have sent, I have readen both and it's very interesting, I am also more confortable in my choice to utilise Defender as an anti virus.

Best regards

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Hi, there will always be false/positives also more chance of a error with that number if scanners. https://www.virustotal.com

I will say that if you have something already on your system by installing or updating it is possible to set it loose. When in doubt https://www.malwarebytes.com/

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7zS.sfx is the 7-ZIP self extractor stub from 7-ZIP that is used by Mozilla to pack the actual Firefox program with the 7-ZIP archive utility. Apparently VTZilla doesn't like this 7-ZIP stub and flags all applications as viruses.

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A small number of Antivirus like Antiy-AVL, Norton and Cylance has done false positives with Firefox on Windows including on virustotal over the years.


Pkshadow said

I will say that if you have something already on your system by installing or updating it is possible to set it loose.

WestEnd said

Not a FF issue but your security program issue. I have no trouble download and installing FF EN from that site.

Not due to any malware on Windows as for example Antiy-AVL is doing a false positive with the French Win64 Firefox 61.0.2 on https://www.virustotal.com/#/file/9734073d0dc233d0c260b8e40178010c1c2bf58bede57dd81e33f17eacefd6dd/detection

It is having a issue with 7zS.sfx as cor-el mentioned if you look in details.

VTzilla is a extension for Firefox for the VirusTotal. https://www.virustotal.com/en/documentation/browser-extensions/

Modified by James

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Pkshadow said

Hi, there will always be false/positives also more chance of a error with that number if scanners. https://www.virustotal.com I will say that if you have something already on your system by installing or updating it is possible to set it loose. When in doubt https://www.malwarebytes.com/

Thank you Pkshadow for your answer.

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cor-el said

7zS.sfx is the 7-ZIP self extractor stub from 7-ZIP that is used by Mozilla to pack the actual Firefox program with the 7-ZIP archive utility. Apparently VTZilla doesn't like this 7-ZIP stub and flags all applications as viruses.

Thank you cor-el, this is a good hypothesis.

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James said

A small number of Antivirus like Antiy-AVL, Norton and Cylance has done false positives with Firefox on Windows including on virustotal over the years. Pkshadow said
I will say that if you have something already on your system by installing or updating it is possible to set it loose.

WestEnd said

Not a FF issue but your security program issue. I have no trouble download and installing FF EN from that site.

Not due to any malware on Windows as for example Antiy-AVL is doing a false positive with the French Win64 Firefox 61.0.2 on https://www.virustotal.com/#/file/9734073d0dc233d0c260b8e40178010c1c2bf58bede57dd81e33f17eacefd6dd/detection

It is having a issue with 7zS.sfx as cor-el mentioned if you look in details.

VTzilla is a extension for Firefox for the VirusTotal. https://www.virustotal.com/en/documentation/browser-extensions/

OK Thank you James, I think that the answer is clear now.

Thank you to every body for your help.

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cor-el said

7zS.sfx is the 7-ZIP self extractor stub from 7-ZIP that is used by Mozilla to pack the actual Firefox program with the 7-ZIP archive utility. …

Defocusing from Firefox, https://github.com/4ian/GDevelop/issues/88#issuecomment-81366849 (2015-03-16) observed:

7zS.sfx is used to create Windows executable that can extract their own contents in a temporary folder: …

7zS.sfx also featured in Mozilla bug 1468067 - Firefox installer doesn't pass VirusTotal test.

An older bug, unassigned: 1199754 - Let's stop packing Windows installer with UPX.

Modified by Graham Perrin