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Why patching can make your Kenna score go up instead of down

Dave Farquhar security September 18, 2019August 25, 2019 0 Comment

Kenna is a revolutionary vulnerability management tool. It completely changed my approach to vulnerability management. But it can be hard to get used to. The most maddening thing about it is how you can deploy an update, and then your Kenna score increases. That’s not the outcome you wanted. Here’s why patching can make your Kenna score go up instead of down, and what to do about it.

Kenna’s math is tricky, but the thing to remember is the risk score isn’t exactly an average. Once you deploy enough patches for high-risk vulnerabilities, your risk score will start to drop as expected. The key is sticking with it long enough for the score to drop.

BIOS hard drive limits

Dave Farquhar Retro Computing September 17, 2019September 8, 2019 0 Comment

Back in the old days, we had to worry about BIOS hard drive limits. I couldn’t put a 40 GB hard drive in my 486 because it couldn’t recognize a drive of that size. Granted, I didn’t want to do that in the 90s, but now that we’re starting to dust off those old systems and put modern storage solutions in them, sometimes we have to think about those limits again.

Generally speaking, older systems tend to be limited to hard drive sizes of 528 MB, 2.1 GB, 4.2 GB, 8.4 GB, 33.8 GB, or 137 GB. Sometimes you can configure the system to ignore the extra size, or you can use another workaround.

How does Nessus detect vulnerabilities?

Dave Farquhar security September 16, 2019August 24, 2019 0 Comment

Nessus is a popular vulnerability scanner, but there are some misconceptions about what it does and how it works. So how does Nessus detect vulnerabilities, and why is that important? Let’s explain.

Nessus detects vulnerabilities in two major ways, either by scanning ports or scanning files. Scanning files requires it to log in to the system, but it is considerably more accurate.

Lionel 184 bungalow notes

Dave Farquhar Toy trains September 13, 2019August 25, 2019 0 Comment

I’ve been buying up Lionel 184 bungalows lately. I picked up my first at a toy show, and probably paid too much for it considering its light didn’t work (and yes, I asked). But then I picked up some 1980s reproductions at an estate sale at a fantastic price, so that more than made up for me overpaying for my first. These tiny houses look great on a layout and they aren’t hard to fix.

What does a Sound Blaster do?

Dave Farquhar Hardware, Retro Computing September 12, 2019August 24, 2019 0 Comment

There was a time when the Sound Blaster, and its manufacturer, Creative Labs, were household names. Today the product is a bit marginalized, even though it’s historically very significant. What does a Sound Blaster do, and should you care?

A Sound Blaster provides audio capability for a PC, usually slightly better than what comes built into modern PCs. Before sound came standard, Sound Blaster was the most popular and best supported type of sound card.

Copy an option profile in Qualys

Dave Farquhar security September 11, 2019August 24, 2019 0 Comment

Since I don’t do it very often, I always forget how to copy an option profile in Qualys. So here’s how, even if I’m the only one who ever can’t remember.

Sometimes I need to make a copy of an option profile so I can make a change to it without building a new one from scratch.
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SD to IDE performance

Dave Farquhar Retro Computing September 10, 2019September 8, 2019 1 Comment

Working IDE hard drives are getting harder to find. Compact Flash cards, the easiest modern substitute, aren’t all that easy to find anymore either. That got me looking at SD to IDE adapters, which convert cheap, readily available SD cards to a legacy IDE interface. This is convenient, but how’s the performance?

It turns out there are three limiting factors in SD to IDE performance: Card speed, adapter speed, and IDE bus speed. But since seek times on SD cards is lower, you can still see a performance improvement over a mechanical drive even if the transfer rates are disappointing. This is especially true of legacy systems that don’t have pre-emptive multitasking.

What does secured mean for Internet access?

Dave Farquhar security September 9, 2019August 18, 2019 0 Comment

Both Windows and your web browser go out of their way to tell you if your Internet connection is secured, or not secured. Secured certainly sounds better than not secured. But what does secured mean for Internet access? Let’s talk about it.

“Secured” is a friendly word to say your network connection is encrypted. But what that means, exactly, depends on whether it’s your web browser or your operating system saying the connection is secure. The most important thing to remember is that in this case, your browser can compensate for Windows, but Windows can’t compensate for the browser.

Lionel’s connection to Marx

Dave Farquhar Toy trains September 6, 2019August 18, 2019 0 Comment

Lionel and Marx were fierce competitors in the postwar, mid-century time period. But since old train tooling never dies, it just changes hands, Lionel’s connection to Marx has grown over the years. Especially in recent years.

Old Marx products found their way into Lionel’s product line when Lionel temporarily took over K-Line. But then, in 2019, some of Marx’s HO scale tooling found its way into Lionel’s revived HO product line.

Confirmed vs potential vulnerabilities in Qualys

Dave Farquhar security September 5, 2019August 11, 2019 0 Comment

When you’re looking at a vulnerability scan, you may find several types of line items on the report. Two of them are confirmed and potential vulnerabilities. Let’s take a look at confirmed vs potential vulnerabilities in Qualys.

Potential vulnerabilities are incomplete, in that they show an indication of vulnerability, but not enough for Qualys to confirm it. Confirmed vulnerabilities are more reliable, as Qualys was able to pinpoint a vulnerable file or setting on the system. In some scan results, Qualys refers to potential vulnerabilities as “practice.” As far as Qualys is concerned, practice and potential are interchangeable terms.

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