⚠️ Warning About Firefox Private Browsing Memory Issue


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jen1

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It's crucial to be aware of a significant privacy concern regarding Firefox's private browsing feature. Currently, you must close Firefox completely to ensure that any private browsing data is cleared from memory. This issue has been reported, but Mozilla has not flagged it as a security risk, which raises concerns about user privacy, especially in networked environments.

🛑 Details of the Issue​

  • Bug Report: A bug has been filed regarding this memory issue, which you can view here. Mozilla has decided not to classify it as a security risk, meaning the resolution may take a long time, if it is addressed at all.
  • Privacy Implications: If you are using private browsing, any data from that session may remain in memory until the browser is completely closed. This could potentially expose sensitive information if the browser is left open after private browsing sessions.

🔒 Recommended Actions​

To protect your privacy while using Firefox, follow these steps:
  1. Close Firefox Completely: Always ensure that you close the entire browser after using private browsing. This action will help clear any residual data from memory.
  2. Stay Informed: Keep an eye on updates from Mozilla regarding this issue. They may eventually address it, but until then, it's essential to take precautions.
  3. Consider Alternatives: If privacy is a significant concern for you, consider using other browsers or privacy-focused tools until this issue is resolved.

📅 Timeline for Fix​

Given that Mozilla has not prioritized this bug as a security risk, it may take months or longer for a fix to be implemented. Users should remain vigilant and proactive in managing their privacy while using Firefox.
By sharing this information, along with the link to the bug report, you can help raise awareness among other users about the potential risks associated with Firefox's private browsing feature.
 

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am only using Firefox for privacy reasons, but with this issue not addressed, especially if you work in a network, we should take measures. Anyone can potentially dump the memory for the Firefox process and access your private browsing data, even if the private browsing is closed. It's crucial to be aware of this risk and take appropriate precautions to protect sensitive information.
 

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Welllll they do say to close all private windows when you're done.
 

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Even if you close all private windows, your previous private data remains in memory (this is the bug). To completely clear private browsing data from memory, you must close Firefox entirely, and then reopen it if you wish. Accessing this data is straightforward; it can be retrieved through a memory dump of the main process.
 

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I suppose this may be worrisome if you think there truly is such a thing as private browsing.
 

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Only if you believe in God or another higher intelligence watching over us, then yes, private browsing is possible and can be achieved. I have been doing it for years ;-)
 

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I do not use it as you do not really gain anything.

Your IP address and online activity are still visible to websites, search engines, and your Internet Service Provider.
 

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jen1 said:
Only if you believe in God or another higher intelligence watching over us, then yes, private browsing is possible and can be achieved. I have been doing it for years ;-)
Click to expand...

No idea what a higher power has to do with web browsers, but you haven't been private browsing, ever. Someone is, or could be, watching over your browsing habits.

jen1 said:
especially if you work in a network
Click to expand...

As KevTech pointed out, your ISP (your employer if you're at work) and the web sites you visit all know about your browsing habits. Private browsing is "don't save these certain things to disk when I'm done," nothing more.
 

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@pseymour I see that you didn’t catch the joke in my previous comment, which was intended to be lighthearted! It’s about privacy, not browsing. If there are higher powers watching over you, then you are not private. It’s a bit frustrating to have to explain a joke, but here we are.
As for private browsing, it’s actually quite achievable. Here’s a breakdown:
  1. IP/Location can be easily masked.
  2. Hardware fingerprints can also be concealed.
  3. Logs and stored data can be avoided.
  4. The most challenging aspect to mask is psychological patterns, which intelligence agencies often use to identify individuals.
There have been numerous hacks where the perpetrators remained unidentified, including breaches involving US intelligence agencies.
If you’re skeptical about private browsing, this thread might not resonate with you.!
 

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As someone who makes jokes a lot, here's a tip... try making them funny.
 

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@jen1
please try in about:config
search bar
cache

disable disk cache enabled set to false
then change
memory cache capacity from the default of -1
to 1048576

close and restart Firefox in private browsing and then check the memory cache retention.

close private browsing and restart Firefox in normal browsing and then recheck the memory cache retention.

you will find that all caching is now cleared with no memory cache retention.

best of luck, Steve ..
 

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@XxXxX This issue is not related to settings; it is a confirmed bug. A solution is expected to be released by Mozilla in the future. For more information, I've included the link to the bug in the opening post.
 

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jen1 said:
@XxXxX This issue is not related to settings; it is a confirmed bug.
Click to expand...

No, but you can use those settings in the meantime until (if or when) Mozilla addresses the issue.
 

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cheaterslick said:
No, but you can use those settings in the meantime until (if or when) Mozilla addresses the issue.
Click to expand...
Please refer to the full bug report for complete context; the link is included in the opening post. This bug was initially flagged as a security risk, but another Mozilla employee has since unflagged it. It's important to confirm the need for Firefox to exist.

I wanted to raise awareness about this vulnerability, but it seems that many have not read the bug report. I won’t be responding further.
 

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jen1 said:
Please refer to the full bug report for complete context; the link is included in the opening post. This bug was initially flagged as a security risk, but another Mozilla employee has since unflagged it. It's important to confirm the need for Firefox to exist.

I wanted to raise awareness about this vulnerability, but it seems that many have not read the bug report. I won’t be responding further.
Click to expand...

Yes and that fix is the workaround to use in the meantime that will clear the cache when you close it.

I rarely ever use Privacy Mode since I never fully trusted it and felt it would disable some of the regular safeguards Firefox had while in normal mode. It's a feeling I've had for years about it.
 

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jen1 said:
@XxXxX This issue is not related to settings; it is a confirmed bug. A solution is expected to be released by Mozilla in the future. For more information, I've included the link to the bug in the opening post.
Click to expand...

i have read the GIT report it is not .. i repeat .. it is not a confirmed bug.
it is a bug report posted by you that has been passed on for review.

best of luck, Steve ..
 

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XxXxX said:
i have read the GIT report it is not .. i repeat .. it is not a confirmed bug.
it is a bug report posted by you that has been passed on for review.

best of luck, Steve ..
Click to expand...
It is a confirmed bug, but Mozilla has not updated the status to 'NEW' as expected. For instance, here is another example of a confirmed bug that was filed two months ago, and its status remains 'UNCONFIRMED. Although it was assigned a priority of 2, it still has not been fixed. You should read the discussion in the bug carefully to understand it. I will not be replying anymore; I just wanted to be helpful and warn those who use private browsing. If you don't use it, you can simply ignore this warning.
 

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jen1 said:
It is a confirmed bug, but Mozilla has not updated the status to 'NEW' as expected. For instance, here is another example of a confirmed bug that was filed two months ago, and its status remains 'UNCONFIRMED. Although it was assigned a priority of 2, it still has not been fixed. You should read the discussion in the bug carefully to understand it. I will not be replying anymore; I just wanted to be helpful and warn those who use private browsing. If you don't use it, you can simply ignore this warning.
Click to expand...
i have been using the gecko engine in one form or another for over 20 years.
this is not a confirmed bug. end of story, so please stop trying to drum up support for your bug report.

best of luck, Steve ..
 

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XxXxX said:
i have been using the gecko engine in one form or another for over 20 years.
this is not a confirmed bug. end of story, so please stop trying to drum up support for your bug report.

best of luck, Steve ..
Click to expand...
Here is a direct quote for the bug report:

If you want to protect against somebody who has access to Firefox's memory after your private browsing session but not during the session, you should restart Firefox.
Click to expand...

This is literally my warning. I'm not sure what you're doing, you're here just to say that you don't use private browsing or that this is not a bug. Please read the actual bug report, or just the quote above

If anyone uses private browsing, closing private windows will keep your private browsing data in RAM. To clear it, you should restart Firefox.

Please stop making comments that have nothing to do with this warning.
 

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While some may dismiss this as a trivial concern, it is a significant issue for those of us working in large organizations with networked environments where many have admin permissions. I used to keep Firefox open for weeks, believing my private browsing was secure, but I’ve since realized that it’s not the best choice for that purpose. I would genuinely appreciate being informed about such important issues.
 

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