Adobe has confirmed that a bug it patched over the weekend is being used by hackers to target Google's GMail users.

According to a Macworld report, 'Cross-site scripting flaws are often used by identity thieves to hijack usernames and passwords from vulnerable browsers. In this case, browsers themselves are not targeted; rather, attackers are exploiting the Flash Player browser plug-in, which virtually every user has installed. Adobe said that Google reported the Flash Player flaw to its security team.'

Adobe strongly recommends all users on all platforms with all browsers using Flash to update their Flash plugins. This also applies to Google Chrome users, which ships with Flash plugin already incorporated.

[ As a side-note, this is one of the reasons why Apple doesn't allow Flash on its iOS devices - the Flash technology is a plugin to the web browser, not a stand-alone application, and it would mean Apple would have to release a whole new iOS update each time Adobe bug-fixed or security-fixed their plugin. ]

Do you have the latest version of Flash installed? Check here!

Apple has acknowledged the MacDefender trojan threat, and has published how to avoid and remove directions in this support article.

There will also be a software update coming shortly that will automatically detect and remove the trojan and its known variants.

Playing Flash content back on a Mac can sometimes be problematic... Read More...

A number of online sources, including the respected TidBits news site, are reporting a bug that seems to have been introduced in the latest Mac OS X 10.6.7 Update.

The full article is here, but the bottom line is that it appears that due to changes in Snow Leopard font security, some OpenType Postscript fonts may no longer render or print correctly, may cause PDFs not to be correctly formed, and may cause application crashes when called.

Whilst this 'bug' doesn't appear to affect applications and processes that use their own printing and rendering engines (like InDesign, for example), those that use the Apple system printing mechanism, like Microsoft Word, or 'print to PDF', may fail.

The recommendation at the moment is not to install this update. If you have installed the update already, there are a number of potential workarounds suggested in the TidBits article, but the only definitive fix at the moment is a system re-install and update as far as 10.6.6, until Apple comes up with a permanent solution.

UPDATE: Apple have now released an update to address this issue.

Summer is well and truly upon us, and as you languish in the heat, spare a thought for your computer, who is also struggling to cope. This past month I've had a number of call-outs to summer-stressed Macs.

One was for a Mac Pro that's been sitting under a desk for a number of years that suddenly would occasionally fail to boot, and when it did, it would hang in the middle of a task.

When I opened it up to look inside, the vents around the fan intakes were choked with fluff, as was the heatsink. After it was cleaned out, I ran a series of hardware tests and found two RAM modules (different makes, different capacities) were failing (causing the boot-up failures), and also the thermal sensors that control the temperature of the processors were also dead, causing the processors to overheat and shut down when under stress, causing the hangs.

Another call out was for an aluminium iMac, that was having display issues and would not boot up. It lived on a desk, back to a sunny window. When I opened up this one, the inside looked like the dust bag of a vacuum cleaner! The vents at the bottom of the screen were totally clogged up with dust, and the single fan that draws air up and pushes it through the chassis was suffocating. The inside of the iMac, especially the graphics card which itself generates a lot of heat had literally 'cooked', and on later inspection, the hard-drive had started to develop bad blocks as was on its way out, too. By placing it in front of the sunny window, clogged with dust and unable to draw cooling air through the chassis or dissipate it through the casing, it had no chance.

Two other call outs were for an older PowerMac G4 and a year-old iMac, both of which would no longer boot up. The problem in both those cases was the power supply had blown caused by power fluctuations. Electrical storms and everyone turning on their aircon units can cause power spikes or surges that can easily blow a power supply in a computer, or big-screen TV or projector, or any other electrical device for that matter. Better the power supply than the logic board!

So what can be done to protect your Macs and other electrical devices during the summer months?

• Basic housekeeping - keep the vents on the top/bottom/sides clear of fluff and other obstructions, so that there is a free flow of air. Turn the device off, and get the vacuum cleaner out and give it a good going over. You'll be surprised just how much dust and fluff accumulates around vents, drawn in by airflow and static. (Whilst you're at it, vacuum your aircon intake vents and replace the filter pad, or you'll overload the fan and it'll stop working efficiently!)

• Don't leave it in the sun, and where possible, use in a cool area. Computers get very hot inside from normal operations, and rely on either fan-forced or passive cooling through their chassis to keep cool. If the ambient temperature is very warm, it's not going to help! As components get hot, they expand, and can crack their solder, causing component failure.

• Get a proper surge protector or UPS and plug your device into that. They are designed to provide your device with a regulated 'clean' power supply, and blow their fuse when there's a surge, putting less stress on, and providing good protection for, your device's power supply unit. I should point out that I sell surge protectors and APC UPS (Uninterrupted Power Supply) products to suit all applications, so please contact me for pricing.

• It's also possible with some Macs to control the internal fan speeds and speed them up to assist with cooling that way. SMC Fan Control is one such piece of software that I've used successfully with some iMacs and laptops to help dissipate the heat. Your mileage may vary - it doesn't work with all models.

• Newer model hard drives have an upper operating temperature of about 60C, older models 50-55C. Given they spin at 5400rpm, 7200rpm or faster, hour after hour, they get hot quite quickly, and if they exceed their safe working temperatures they too can 'cook' and fail, potentially taking your data with them. You can monitor aspects of your Mac's internal temperatures with the shareware iStat Menus or freeware atMonitor or Temperature Monitor.