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Is Firefox lying to users about viruses in downloads?

theindy.us

31–40 of 76 posts

Re: Is Firefox lying to users about viruses in downloads?

#31
post #23
post #13

Earlier quoted context omitted.

I wonder why they can’t integrate some service like VirusTotal into their downloader. Sure, for heretofore new objects it’ll take longer, but they have a long list of many many file hashes and their reputation dB .

There are quite a few reasons I can think of: * Privacy * Performance * They would likely have to work with Virus Total to support their infrastructure as I can only imagine how quickly they'd take such a cloud service offline if everyone started using it by default * And then what happens if / when the cloud service does have an outage? Does that mean people are blocked from downloading things? * Same question for p…

Those are good things to think about, but I'll give them a stab:

_Privacy: They [FF] can act as anonymous proxy.

_Perf: Yes, for new objects, but for known objects, it should be minimal.

_Service outage: Build a system which can allow an override (download at your own peril, while service is out)

_Corp should already have enterprisey systems in place

_New, unknown object: Yes an issue.

As someone else said [GlitchMr], if they can do it ala haveibeenpowned I think it's worth looking into.

Re: Is Firefox lying to users about viruses in downloads?

#32

Earlier quoted context omitted.

... so, materially yes? As a user, I don't care that they have an excuse, I care that they said "this file is a virus" when the file was not a virus.

Not really. "Lying" includes an intent to deceive. I would have been okay with "raises false alarms", "generates false positive" or even "confuses and/or misleads users". As a user, I want to be better safe than sorry - but would perhaps be happier with a finer classification than "no problem/OMG VIRUS!"

Until the moment where you really need that file.

Re: Is Firefox lying to users about viruses in downloads?

#33
post #16

Earlier quoted context omitted.

... so, materially yes? As a user, I don't care that they have an excuse, I care that they said "this file is a virus" when the file was not a virus.

Having false positives != lying.

Not inherently, but in this case all positives are matched to the same wording, and that wording expresses 100% certainty to the user that something in the file will harm their computer. That's a lie, because that is not what has been determined at all.

Re: Is Firefox lying to users about viruses in downloads?

#34

There are several ebooks that have been uploaded to libgen that contain PDF exploits, and from what I understand there's no way to remove them. The way that their library database works is by linking a book number to a file's md5 sum. On the filesystem they are stored something like `$drive:\$batch\$sum` where `$drive` is a Windows drive letter, `$batch` is the primary key of the document rounded to the nearest 1k, 1…

I could be wrong but I think technically a PDF exploit only affects a single viewer program, like Acrobat on windows, right?

Re: Is Firefox lying to users about viruses in downloads?

#36
post #13
post #6

Firefox isn’t necessarily scanning the files for viruses, they’re often just using databases that list domains suspected of hosting malware. IIRC, Chrome does the same thing too. I think it's not much of an issue for Firefox to flag stuffs downloaded from suspected URLs as a malware since it's not uncommon to have one's system infected from those sites' content. Firefox is just trying it's best to prohibit any sort o…

I wonder why they can’t integrate some service like VirusTotal into their downloader. Sure, for heretofore new objects it’ll take longer, but they have a long list of many many file hashes and their reputation dB .

cue the inevitable "Firefox is leaking every file you downloaded!"

Re: Is Firefox lying to users about viruses in downloads?

#37

I'm not as bothered by the main point of the article but it does raise an interesting point that was missed by the comments so far is near the end: If you're flagging files as potentially harmful, giving a user a choice to either execute it or delete it is kind of bad design!

No, it's not "bad design".

If there's an uncertainty in detection, there are false positives and letting the user decide is the only correct option.

Edit: Nevermind. Re-reading the article - they should indeed allow saving the file in addition to deleting or opening it.

Re: Is Firefox lying to users about viruses in downloads?

#38
post #31
post #23

Earlier quoted context omitted.

There are quite a few reasons I can think of: * Privacy * Performance * They would likely have to work with Virus Total to support their infrastructure as I can only imagine how quickly they'd take such a cloud service offline if everyone started using it by default * And then what happens if / when the cloud service does have an outage? Does that mean people are blocked from downloading things? * Same question for p…

Those are good things to think about, but I'll give them a stab: _Privacy: They [FF] can act as anonymous proxy. _Perf: Yes, for new objects, but for known objects, it should be minimal. _Service outage: Build a system which can allow an override (download at your own peril, while service is out) _Corp should already have enterprisey systems in place _New, unknown object: Yes an issue. As someone else said [GlitchMr]…

>_Privacy: They [FF] can act as anonymous proxy.

I think he's talking about the file contents.

Re: Is Firefox lying to users about viruses in downloads?

#39

I'm not as bothered by the main point of the article but it does raise an interesting point that was missed by the comments so far is near the end: If you're flagging files as potentially harmful, giving a user a choice to either execute it or delete it is kind of bad design!

No, it's not "bad design". If there's an uncertainty in detection, there are false positives and letting the user decide is the only correct option. Edit: Nevermind. Re-reading the article - they should indeed allow saving the file in addition to deleting or opening it.

The implied better alternative is to allow saving, instead of opening, so users can scan the files themselves.

Re: Is Firefox lying to users about viruses in downloads?

#40
post #21

If only the voting public understood about statistics, false positives, and false negatives. Even if Firefox did a full virus scan, there would still be false positives and false negatives in the results. The system designer always has to put their reporting threshold somewhere, and that always means making a decision to bias towards false positives or false negatives. Eliminating false positives means exploding the…

Unfortunately people like yourself feel the need to respond to articles without reading them first.
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