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1

Individual watermarking by a webserver application can be done in a way that is invisible to the eye of the user downloading it. If individual watermarking is applied, it will lead to different files having different hash-signatures. But it can be done in a way, that makes an image unusable (meaning havily reduced in quality) if the file is downloaded ...


1

Given your requirements, i'd consider doing all of my web browsing in a VM. You could keep it up to date, and then after your session simply restore a snapshot. Update Windows or what have you only, then create new snapshots as patches become available. I do this myself to avoid malware accessing my sensitive data.


1

Today (windows) computers are usually are fairly good locked against direct attacks from the network by default, at least if you specify that you are on a public network. That means they have a firewall, don't expose unneeded services to the outside etc. I am not too concerned about being "attacked" as my computer's are mainly gaming and internet (Social ...


9

Usually the PNG format does not support multiple layers. So when you draw over something, whatever was there before is lost. However, the PNG format supports storage of an unlimited amount of metadata which is usually not displayed by image viewers. This feature is often used by image editors to add additional metadata to the image. One possible use-case is ...


3

When you paint over a jpg or png file, you are not putting a sticker over the image, you are more ripping a hole on the image and filling the hole with ink. Even on Photoshop, if you export the picture as jpg it will flatten the image, merging all layers together and destroying the original obscured area forever. There's no way to reconstruct the original ...


2

No, the security is no better. The typical formats used for screenshots (JPEG or PNG) are not image formats that support layers like say, a PSD does. When you add the green scribble, you're not adding a layer, you're replacing part of the image. The extra step, the screenshot-of-a-screenshot should give you an image file that's materially the same. ...


0

This really is dependent on the language, if it's compiled then what compiler was used. The question is... how secure is the value stored in "plainText" (at REFERENCE 1)? Without using a special secure class this variable will reside in memory until it is overwritten. Not all languages provide a "secure class" for data. Freeing memory does not ...


0

You are right, this is a common problem for code handling sensitive data. In the .Net managed environment, even if you zeroed out your string, you would still run into problems, due to movement of the string as a result of garbage collection. The garbage collector wants to defragment the heap and therefore can move your string around. Moving of course ...


-1

In .Net you can use secure string to have some level of protection against memory reading like that : http://msdn.microsoft.com/en-us/library/system.security.securestring(v=vs.110).aspx


0

The standard infosec response to complete compromise like this is to nuke it and start all over again, but this time from a security-hardened position. If you have many interconnected devices that are habitually insecure (they all have the same password, for instance), then you need to disconnect them from everything else, wipe them, secure them, then ...


1

Regardless of what is contained in the paper a standard ntp request datagram does contain a timestamp that represents the time the datagram was sent. From page 22 of the RFC: Origin Timestamp (org): Time at the client when the request departed for the server, in NTP timestamp format. The answer to the question "Does ntp leak system time?" is "Yes. A ...


1

First, use a known clean computer (not related to anything you had and not connected to anything you have now) to clear up all your online presence, especially various cloud storage services such as icloud/googledrive/dropbox/onedrive. Close up any unneccessary accounts and get your email in order - it often is the key point that must be secure. Set up two ...


2

No, the paper means something else. The paper talks about connecting multiple times to the same Tor Hidden service to increase the load, and at the same time measuring clock skew from candidate IP addresses. If the candidate shows clock skew during the attack, the server can be identified.


5

I believe the term you're looking for is a "canary trap", which is a form of offensive counterintelligence. This is similar to a suspected double-agent being given false information, which they then leak back to their handlers. This can then be used to show that the agent, being the only one told that information, was the real leak.



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