Need help sorting out how to use 23? Or have you discovered one of those nasty bugs?


Kilessan   May 01, 2012, 07:40 AM


pardon me for starting a public conversation on this, but I just received a notification for a new thread in the help group apparently involving one of my photos. It seems someone's antivirus software flagged a jpeg as malware? However, I do not usually give access to the original pictures, so the 'infected' images were resized versions (i.e., resized by 23)... and the original was more or less straight out of my raw converter. Someone seems to have done something, though: in my photo stream, the corresponding image's thumbnail briefly looked broken (perhaps the image was blocked briefly).

Now everything seems to be fine again, and the conversation in question even seems to have been deleted. So, should I worry about anything? As far as I can tell, my computer is malware-free, and I make a point of my uploaded content being 'clean' both with regard to the files and their content, anyway.


Steffen Fagerström Christensen Team 23   May 01, 2012, 08:02 AM

Hi Robert,

I deleted the conversation because it had a nature of spam (mentioning product names, including links) -- so that's one question answered. And then you're absolutely right that the reference to a problem mentions a rescaled photos, meaning that we're talking about a straight JPEG image. And yes, I would worry about your computer being malware-free in this context.


Kilessan   May 01, 2012, 08:14 AM

At least I scan regularly with different tools, yet the last incident has been several years ago. So I assume everything should be all right at this end. Thank you for the info.


mate-fotos   May 01, 2012, 08:49 AM

@Steffen: It was not my intention to spread spam. I just wanted to point to a safety problem. I will not mention any product names in the future. Sorry...

@Robert: Currently, the problem still exists ... Why didn't you erase the image and upload a new version of it again?
I hope your computer is really malware-free, but I fear he isn't.


Kilessan   May 01, 2012, 09:28 AM

What I was trying to point out is this: the images you linked to are resized versions. In other words: these images are generated by the server, not by me. You simply do not have access to the original image. Furthermore, all images in the album (16 in total) have been converted in a timespan of under an hour, on the same machine and using the same software.

So, at the moment I see two possibilities. First possibility: I have indeed malware on my computer which (1) has not been found by regular scans using three different scanning tools, which (2) has infected 1 but not the other 15 images I uploaded during the same session, and which (3) produces an "infection" in a JPEG (which is not an executable file anyway) that (4) furthermore survives the automatic rescaling/conversion process performed by the 23 server. In this case, simply re-uploading the file like you suggested would not work anyway.

The second possibility would be: the detection heuristic of your antivirus software simply produced a false alarm. This happens and BTW is a significantly simpler explanation, since it involves only one variable, not 4 or more like the other. I will re-check my machine this evening, but at this moment I am (following Occam's razor) tending towards explanation #1.


PS: you could consider forwarding the image link(s) in question to the manufacturer of your security software. They will (hopefully) be able to tell whether it is a false alarm or not (and if it is, adjust their detection algorithm accordingly).

Kilessan   May 01, 2012, 10:23 AM

Final (at least for me) note: it _is_ a false positive. I just ran the 'large' resized version through It shows indeed a detection of "Exploit/MS05-036.gen", but exactly from 1 out of the 42(!) tested scanners.

Then I checked the original file. Downloaded from using a Linux machine, then uploaded to And guess what? 0 (zero) hits. ;)

So this really appears to be glitch in your security software.


mate-fotos   May 01, 2012, 12:31 PM

Thank you for the work you've done and apologize for the circumstances which I have prepared for you.
It actually seems to be a fault in my security software.


Kilessan   May 01, 2012, 06:10 PM


it's really no problem. Better be safe than sorry, especially when data security is concerned. If anything you have caused to re-check my system in extra-paranoid mode, which is also not necessarily a bad thing. ;)



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