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Why did firefox start uploading data from my computer (150 MB or more)?

  • 2 replies
  • 1 has this problem
  • 25 views
  • Last reply by rlhospe

rlhospe
rlhospe
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I was logging into Google hangouts this evening when I noticed that Netlimiter was indicating a high upload rate, about 300 kB/sec, which is higher than my usual download rate. Firefox was indicated as the application responsible, and I throttled it down to 5 kB/sec and then shut it down completely before the upload behavior stopped. Another net utility I use indicated that firefox had uploaded 150 MB in that short time span.

I've been performing scans with Norton and MWB and getting negative results. I'm also not getting any results searching on google for exfiltration techniques using browsers. Any idea what's going on? I really don't like the idea of someone being able to suck massive amounts of data from my computer with the connivance of this browser.

I was logging into Google hangouts this evening when I noticed that Netlimiter was indicating a high upload rate, about 300 kB/sec, which is higher than my usual download rate. Firefox was indicated as the application responsible, and I throttled it down to 5 kB/sec and then shut it down completely before the upload behavior stopped. Another net utility I use indicated that firefox had uploaded 150 MB in that short time span. I've been performing scans with Norton and MWB and getting negative results. I'm also not getting any results searching on google for exfiltration techniques using browsers. Any idea what's going on? I really don't like the idea of someone being able to suck massive amounts of data from my computer with the connivance of this browser.

All Replies (2)

Mick
Mick
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Hi rlhospe,

Take a look at this article: How to stop Firefox from making automatic connections it may help :)

Modified by Mick

rlhospe
rlhospe Question owner
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If uploading telemetry data can result in uploads of hundreds of MB, then that answer seems plausible. I've turned off the permissions for "Firefox Data Collection and Use" in Options. I don't feel satisfied that this action will stop a recurrence of the observed problem, but it's worth a try. Thanks.