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MalwareBytes Detects Safe File All the Time.. What to do?

  • 12 replies
  • 1 has this problem
  • 12 views
  • Last reply by user1469512

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When i run Malwarebytes it identifies 'pref.js' in the firefox directory as unsafe on the latest FF 64 bit 63.0.3. I then choose the option to quarantine it even if its a needed and safe file thats part of firefox. When I run Malwarebytes again, it detects it again! Malwarebytes fails to quarantine it, if its supposed to do that. Should I leave this file alone?

When i run Malwarebytes it identifies 'pref.js' in the firefox directory as unsafe on the latest FF 64 bit 63.0.3. I then choose the option to quarantine it even if its a needed and safe file thats part of firefox. When I run Malwarebytes again, it detects it again! Malwarebytes fails to quarantine it, if its supposed to do that. Should I leave this file alone?

All Replies (12)

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The prefs.js file stores customized settings, so it's difficult to know why Malwarebytes is suddenly upset about it. Does Malwarebytes give any specific information about what it doesn't like in the file?

Also, don't remove prefs.js while Firefox is still running.

If you let Malwarebytes remove prefs.js while Firefox is closed, at the next startup, your settings should be back to default (e.g., built-in home page, no new tab page pinned tiles, original preferences values, etc.), but you will still have your saved bookmarks, passwords, and add-ons.

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jscher2000 said

The prefs.js file stores customized settings, so it's difficult to know why Malwarebytes is suddenly upset about it. Does Malwarebytes give any specific information about what it doesn't like in the file? Also, don't remove prefs.js while Firefox is still running. If you let Malwarebytes remove prefs.js while Firefox is closed, at the next startup, your settings should be back to default (e.g., built-in home page, no new tab page pinned tiles, original preferences values, etc.), but you will still have your saved bookmarks, passwords, and add-ons.

Hi,

To answer your question, MB's report said this:

"File: 2 Trojan.Agent.CK, C:\WINDOWS\SYSTEM32\TASKS\OINSTALL, Quarantined, [4440], [400551],1.0.8153 PUP.Optional.Conduit, C:\USERS\Z\APPDATA\ROAMING\MOZILLA\FIREFOX\PROFILES\O182YAT8.NEW\PREFS.JS, Replaced, [215], [301520],1.0.8153"

What do you think?

Modified by user1469512

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koolx said

... PUP.Optional.Conduit ...

Conduit is associated with numerous "potentially unwanted programs" (PUPs), including some browser extensions. I'm not sure which extensions you have installed, but it's worth reviewing.

You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

  • Ctrl+Shift+a (Mac: Command+Shift+a)
  • "3-bar" menu button (or Tools menu) > Add-ons
  • type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions.

Then cast a critical eye over the list on the right side. Any extensions Firefox installs for built-in features are hidden from this page, so everything listed here is your choice (and your responsibility) to manage. Anything suspicious or that you just do not remember installing or why? If in doubt, disable (or remove).

Any improvement?

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jscher2000 said

koolx said
... PUP.Optional.Conduit ...

Conduit is associated with numerous "potentially unwanted programs" (PUPs), including some browser extensions. I'm not sure which extensions you have installed, but it's worth reviewing.

You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

  • Ctrl+Shift+a (Mac: Command+Shift+a)
  • "3-bar" menu button (or Tools menu) > Add-ons
  • type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions.

Then cast a critical eye over the list on the right side. Any extensions Firefox installs for built-in features are hidden from this page, so everything listed here is your choice (and your responsibility) to manage. Anything suspicious or that you just do not remember installing or why? If in doubt, disable (or remove).

Any improvement?

Hi,

I looked over the extensions and I dont really suspect any that stand out as hazardous. Check out my list of addons and let me know what you think. Thank you:

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I've heard of Stylus and uBlock Origin.

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jscher2000 said

I've heard of Stylus and uBlock Origin.

So youre saying I should remove Stylus and uBlock Origin? But I need these addons

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koolx said

jscher2000 said
I've heard of Stylus and uBlock Origin.

So youre saying I should remove Stylus and uBlock Origin? But I need these addons

Just Disable them and see what happens.

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koolx said

jscher2000 said
I've heard of Stylus and uBlock Origin.

So youre saying I should remove Stylus and uBlock Origin? But I need these addons

No, those are the ones I have heard of. Meaning those should be fine. The others are the ones I don't know anything about.

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jscher2000 said

koolx said
jscher2000 said
I've heard of Stylus and uBlock Origin.

So youre saying I should remove Stylus and uBlock Origin? But I need these addons

No, those are the ones I have heard of. Meaning those should be fine. The others are the ones I don't know anything about.

I ran this question on the malware forum. Someone said I should reinstall firrefox which is what I'm doing now.

Btw, would you please answer my thread here: https://support.mozilla.org/en-US/questions/1243139

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Could you paste here the content of this prefs.js file?

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koolx said

Btw, would you please answer my thread here: https://support.mozilla.org/en-US/questions/1243139

I never connected Thunderbird to a Gmail account, so I have no idea.

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jscher2000 said

koolx said
Btw, would you please answer my thread here: https://support.mozilla.org/en-US/questions/1243139

I never connected Thunderbird to a Gmail account, so I have no idea.

Thanks any way..