Editor's note: Chester Wisniewski is a senior security adviser at Sophos Inc., Canada. He researches computer security and privacy issues and is a regular contributor to the Naked Security blog. The opinions expressed in this commentary are solely those of the author.
(CNN) -- This week, researchers from Google and the Finnish security consulting group Codenomicon disclosed a bug, called Heartbleed, in OpenSSL, one of the most ubiquitous encryption software packages in use on the Internet.
Two thirds of the web sites and applications that allow you to do online banking or communicate privately through e-mail, voice or instant message use OpenSSL to protect your communications.
That is why a bug in OpenSSL that can render the private information you are transmitting across the wire visible to attackers is a very big deal.
The bug itself is a simple, honest mistake in the computer code that was intended to reduce the computing resources encryption consumes. The problem is that this bug made it past the quality assurance tests and has been deployed across the Internet for nearly two years.
This brings into question all the secure conversations we thought we were having on affected services over that time. A big deal indeed.
How does something like this happen? Aren't there a lot of people looking at this code? It is open source after all; anyone can take a peek.
Usually the availability of source code to public scrutiny results in applications being more secure and one could argue that is what happened here. Researchers at Google were looking carefully at the code and discovered this mistake. Unfortunately, that discovery came two years too late.
Fortunately, most major Web services have already applied fixes to the affected Web servers and services. The bad news is that smaller websites as well as many companies' products that rely on OpenSSL may linger for many more years without a fix.
To a degree, we are at the mercy of the website operators and companies who make security products to apply these fixes to protect us.
Some are suggesting that everyone should change all their passwords. While it is never a bad idea to change your passwords, increase their strength and ensure they are sufficiently unique, you should only do this after confirming the site has been fixed.
Too little attention is paid to the critical nature of the free software that keeps the Internet moving. We expect this army of volunteers to write and maintain much of the code that enables our fast and free Internet, all without payment, without support, in essence without a thought.
Recently, companies like Google have begun making an effort to rectify this situation through programs like Patch Rewards. Google offers to pay researchers to find bugs in commonly used open source software, including OpenSSL, so the community can work together to fix flaws more quickly, resulting in a safer Internet.
All of us have come to rely on the Internet socially, politically and economically. The billions of dollars a year being made by the tech giants would not be possible without the millions of donated hours that maintain free and open software like OpenSSL, Linux, Apache Web server, and Postfix mail server.
Businesses, government and individuals all have something to offer that can help. This isn't a battle between Windows, Mac and Linux or some battle between free and commercial software. This is a fight for our privacy, security and our freedom to communicate.
For some of us what we can offer is coding talent, others financial support, and still others can test software more thoroughly to ensure the reliability and security of the resulting code.
The most important thing is to recognize the importance of our collective security and to realize that in the end we are all tangled together online. A weakness in one can affect us all.
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