Firefox is a Web browser that is smaller, faster, and in some ways more secure than the Netscape browser from which much of its code was derived.

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16
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3answers
1k views

What security risks does Firefox 19's built-in PDF reader (pdf.js) bring?

Firefox 19 ships with pdf.js as the default PDF reader. One of the main stated goals is to reduce the exposure of users to the often vulnerable Adobe PDF reader/plugin. So what new risks does pdf.js ...
15
votes
4answers
721 views

Firefox pre-downloading

I've found out that if you download a file with Firefox, a similar window as this one pops up (in dutch in my case): ("Bestand opslaan" = "Save file") However, the file is already being ...
15
votes
3answers
736 views

Are official browser add-ons really safe?

Almost any browser addon/extension that I install on my Chrome or Firefox (be it Firebug, RESTClient, ...) warns me, saying: It [the add-on] can: Access your data on all website Access ...
11
votes
2answers
408 views

What should I look for when auditing a Firefox extension / plugin?

I've been asked to do a security audit on a Firefox add-on developed by a third party. I am a web developer with a reasonable grasp of JavaScript but am not a browser security expert. What kinds of ...
10
votes
2answers
912 views

Can a Firefox add-on or plug-in access the user's websites' saved passwords in decrypted mode?

Going deeper into the previous question on Firefox plugins and add-ons malware risks: Could a Firefox add-on potentially decode and capture the encrypted websites' passwords saved in the browser?
10
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2answers
556 views

Any tool for scanning vulnerabilities in browser extensions?

I am scanning browser extensions of Chrome and Firefox for vulnerabilities. Is there any tool which would help me do this?
7
votes
2answers
13k views

How do some sites detect AdBlock Plus? [closed]

For example this one disables function if AdBlock plus is detected, and it works. Is there a way to circumvent this?
7
votes
2answers
298 views

Do I have to harden IE if I'm only using Firefox?

Assume a Windows 7 system (probably whatever home version comes with the machine), with the latest OS patches, latest IE and latest Firefox. Also assume that the user uses only Firefox for browsing, ...
7
votes
2answers
1k views

Is “Fingerprint Check” enough to verify HTTPS certificates?

So I'm at place A, see this sign: and I'm writing the fingerprints to a piece of paper (this website is just an example): Ok. Then, I go to place B (other country, etc.) then I check this ...
6
votes
1answer
130 views

Why does Firefox split HTTPS request?

I am using Firefox browser version 28.0. To access https://www.yahoo.com, I put a proxy with a self-signed certificate in between and my client PC can access the HTTPS site. I then sniffed traffic in ...
6
votes
1answer
398 views

Comparison between Firefox password manager and chrome password manager

As a follow up to Is saving passwords in Chrome as safe as using LastPass if you leave it signed in?, I would like to know how firefox's password manager compares, if you have a master password and ...
5
votes
5answers
561 views

HOWTO : Email encryption in a browser

I have read about encryption and I think it's a good idea for me to encrypt my email. I run ubuntu 12.10 and use Firefox for browsing. In my quest for learning how to use gmail/hotmail to send and ...
5
votes
1answer
208 views

Is this a security flaw in Firefox 18.0?

I had a couple of .mht files which opened in IE, a browser I never use. I renamed their extension to .HTML to run it in Firefox. When I opened the file in Firefox, Firefox created new tabs endlessly. ...
5
votes
3answers
602 views

How to sandbox Iceweasel (Firefox) on Debian? [closed]

Are there any tools for sandboxing Iceweasel (Firefox) on Debian systems? I'm mostly interested in tools distributed by Debian. (An equally trustworthy source would be second best.) (I suppose that ...
4
votes
2answers
146 views

Can webpages recognize that I saved my password?

If you save your logins in Firefox, username and password are auto-filled-in in corresponding webpages as soon as you visit them (if you have more than 1 account saved, you'd have to select a username ...
4
votes
1answer
517 views

Why did firefox remove Javascript injection on address bar?

Why did firefox remove Javascript injection on address bar? Someone said it was a security issue. What security issues could there be?
4
votes
2answers
2k views

Password management in Firefox, Chrome and Safari

I just read a couple of very interesting discussions on Chrome password security strategy. Chrome’s insane password security strategy Showing stored passwords - Tim Berners-Lee The following is how ...
4
votes
2answers
98 views

How do I check if a script is safe to run?

I've been using NoScript for a couple of years now but I can't seem to figure out which scripts are safe to allow and most of the time I just temporarily allow all the scripts. Is there a way to check ...
3
votes
1answer
336 views

I accidentally installed an adware filled Firefox [solved]

I installed Firefox using a download site, rather than the correct site. After running and installing Firefox I noticed my Chrome had an addon called swift browser added to it by a third party. After ...
3
votes
4answers
702 views

FireFox's restore previous session restores logins authenticated by server's sessions

In a website I'm building when I login, close FireFox, open FireFox and try to go to the website again I must login again (as expected) BUT if I select "Restore Previous Session" I am logged in again. ...
3
votes
2answers
2k views

Do most browsers handle mixed encrypted and unencrypted content correctly?

In Google Chrome, when I go to an encrypted page that contains unencrypted content, I get the following pop-down, which allows me to either load or not load the insecure content, making a clear ...
3
votes
2answers
2k views

How does Firefox securely store my SSL certificate?

I'm currently testing a free personal SSL certificate (S/MIME client / authentication) from https://www.startssl.com, which installed directly into Firefox. Now when I store backup, I have to enter a ...
3
votes
2answers
522 views

how to view extension privileges in firefox

In Google Chrome, I can go to chrome://extensions/ and click "permissions" to view the permissions that an installed extension has been granted. I cannot find an equivalent in Firefox. Is there such ...
3
votes
2answers
142 views

Why firefox shows some connections are not secure?

I am using internet by connecting mobile phone to my laptop using usb. From yesterday,my browser (firefox) shows for all most all website. Why this happen? How can i solve this?
3
votes
1answer
220 views

Why warning sign when visiting https-website? [duplicate]

Sometimes when I visit a website using HTTPS, I get a warning sign next to the URL in my browser (see screenshot; look for yellow/orange arrow) and I wonder if this marks a potential threat or an ...
3
votes
1answer
2k views

Firefox Flash plugin malware?

I am running firefox 11 on ubuntu 10.04 and every time I close the program it continues to run in the background. What worries me even more is that the flash plugin is also running in the background: ...
3
votes
3answers
798 views

If I use a good Master Password in Firefox, is security improved when I Remember Passwords instead of re-type?

In the old days I would emphasize that people should not select the remember passwords option because (besides the fact you tend to forget what the browser remembers) a bad guy could could display the ...
2
votes
1answer
247 views

FireFox Download Source

While downloading the latest version of Firefox for Mac, i took a peek at the source. The names don't look legit but i am not that familiar with how CDNs work. I hit download multiple times and ...
2
votes
2answers
2k views

Can Tamper Data (the plugin) modify multipart requests?

I'm doing some testing on my web app with Tamper Data. I've had success with Tamper Data in the past for normal HTTP post requests, but in this particular case I want to modify a post request that ...
2
votes
1answer
387 views

How Browsers prevents Malware and Phishing attacks

I want to know how phishing and malware protection features are implemented in modern browsers like Chrome, Firefox, IE etc. Are these features heuristic based, or do browsers maintain a list of ...
2
votes
4answers
229 views

How to block web-sites from viewing browsing history within firefox?

How can I block websites in Firefox from viewing my browsing history within my browser cache? For example; I've done some Google searches that Amazon is now starting to use to target advertise; the ...
2
votes
1answer
542 views

Different SSL states as seen by Safari, Chrome and Firefox

Today, I visited some sites of the German DHL group. While Chrome and Safari complain about an invalid certificate of Firefox accepts it. Which one is right, which one is wrong? Which decision ...
2
votes
2answers
679 views

Username and password stored under form data in Chrome Dev Tools

When I record the network tab in Chrome Developer Tools when logging in to my site I find that the username and password are stored in plaintext under form data. You can also find it in Safari, ...
2
votes
1answer
67 views

How Do I Troubleshoot a Browser Hijack on a Mac?

My Mac is getting weird redirects with Safari and Chrome, however not with Mozilla Firefox. Since I cannot find software to do malware removal on Apple products or any good information, I am at a loss ...
2
votes
1answer
78 views

How does the Perspective addon work?

I've just installed the Perspetive addon in firefox. When I'm vistit, for example google, Perspective says the following message: Warning: Perspectives has NOT seen this certificate consistently. ...
2
votes
0answers
72 views

Does Firefox support TLS on non-standard ports? [migrated]

My presumption was that TLS 1.0+ is supported by Firefox on ports other than 443. However, a tweet crossed my path that seems to debunk this. Turns out that Firefox does not support TLS on any ...
2
votes
2answers
56 views

Steps after getting hit with malware or browser exploits on Xubuntu

Well, today I was browsing the internet and I suddenly got redirected to a chinese hosted malware site and firefox started going crazy. I checked the url on virustotal with my phone and it found other ...
2
votes
0answers
161 views

Some http requests are not send encrypted by vpn! Why?

I subscribed to a VPN service recently, and installed wireshark to take a look at the traffic sent from my computer. Practically all of it goes through UDP protocol, encrypted. But there are two HTTP ...
1
vote
3answers
450 views

Should I use a Firefox master password or NTFS encrypt my profile?

As a follow-up to another question, is the encryption via Firefox' master password more secure than simply NTFS encrypting the profile folder? I.e. is there a convincing reason to add the ...
1
vote
2answers
100 views

How to sign and encrypt mails using firefox

There is an option under Tools>options>Advanced>Security Devices. How to use that to encrypt and digitally signed your emails.
1
vote
1answer
98 views

How to force browsers to accepte all further SSL certificates

I am using the last versions of IE, Firefox and Google Chrome web browsers on Windows 8. How can force these browsers to accept automatically the SSL certificates of any website I will visit ? I know ...
1
vote
2answers
12k views

Error code: sec_error_untrusted_issuer

I need help with a security issue concerning this code that has just been popping up recently as I visit my favorite websites. Based on some past history I KNOW something is not right, and I am not ...
1
vote
1answer
142 views

How to harden a “dedicated” Firefox?

I want to set up an instance of Firefox to be used to access a strictly limited "white list" of websites (my bank's, my credit cards', etc.). How can I harden such an instance of Firefox to reduce ...
1
vote
1answer
198 views

Canvas and Firefox

I have received this notification on Tor Browser (Firefox). What is it?
1
vote
2answers
63 views

Do browser add-ons increase security risk due to possible vulnerabilities

A large amount of people use add-ons such as NoScript or AdBlock to avoid exploitation by malicious JavaScript from advertisments. This decreases the risk of becoming the victim of web-exploits. But ...
1
vote
1answer
38 views

Preventing tracking in browsers by setting HOME directory

Following worked on Ubuntu 12.04 using chromium and firefox browsers. I ran following command on terminal for both firefox and chromium browser HOME=/tmp/tmpdir firefox Both browsers promptly ...
1
vote
1answer
386 views

Which is a safe way to record Firefox passwords in Gnome Seahorse Keyring?

Here is a question that I asked on "AskUbuntu" and I've been suggested to ask it here: Searching for answers about ways to record Firefox passwords in Gnome Seahorse Keyring vault, I found severals ...
1
vote
2answers
265 views

Is it possible to block third party cookies but allow them when they are first party?

I have been using Cookie Monster in Firefox for a while now to great satisfaction. However, I haven't found a way to allow cookies like Google's on Google's services but block them when I visit other ...
1
vote
1answer
344 views

Trying to verify my X509 certificate “could not verify this certificate for unknown reasons”

I have created my own X509 certificate with my own CA. I am able to import the CA certificate into Firefox, but when I try to import the user's certificates i get the following: "Could not verify ...
1
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2answers
30 views

Xubuntu guest session security

lately I've been using the guest session on my xubuntu install because I am lazy and I was wondering what the security implications can be on the rest of the system if there is a web browser exploit ...