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31

Yes. As you seem to be using a modern terminal emulator, some escape sequences could be used to modify Keyboard buffer. There could be injected proper shell commands. You could use argument -e of cat for safe operation, see man cat. Addendum In fact, it was possible, but in a very old past... As this become an issue, this kind of features was quickly ...


8

I am running LMDE as a workstation and I am afraid as of now (Wed Apr 9 11:28:14 UTC 2014) no patch has been released yet. All available patches have been applied by me and right now # openssl version -a shows OpenSSL 1.0.1e 11 Feb 2013. You might want to consider changing your sources to point to Debian repos directly in order to get the update. I'll be ...


8

Yes, it's a potential risk, see CVE-2003-0063, or CVE-2008-2383 or CVE-2010-2713, or CVE-2012-3515 or OSVDB 3881, or CVE-2003-0020 or any of the similar ones listed here... Some more in comments below also. Update it's not just a potential risk, it's a real risk. The current version of a popular terminal emulator has this problem, resulting in user-assisted ...


6

Typically there is no vulnerability, but obviously if you use it wrong, then you could create one. Printing the contents of a binary file produces beeps because character 7 is the old terminal command to make the machine beep, and some terminal programs still honor that command. But by design, there's nothing there that can hurt you. In the worst case, ...


5

"Real" glass terminals had an escape sequence to print the screen to a printer. They did this by running a command and pipeing the current screen contents to the printer's stdin. The command could be configured by another escape sequence. The classic way of exploiting this was to create files with names that embedded the escape sequence to set the printer ...


5

Basically it is not safe. As far as I know, they use 512-bit RSA because they mimic what Microsoft's RDP server used to do, which indeed implied a 512-bit RSA key; using something bigger would risk breaking compatibility with existing clients. Biggest issue, though, is not that the 512-bit key is weak because too short; the main problem is that, as a client, ...


5

I've already answered this question a few times here. Have a look at this answer in particular: Virus scanner on server And in particular this part: The concept of a virus implies a user at an interactive session. Someone opening email in Outlook or documents in Word, or running programs they received in an email. A virus implies a human element. ...


4

When you are going to play games you downloaded from the internet, you should definitely get a virus scanner. This is especially a concern when you download pirated copies, because these are bundled with malware from time to time. But even when you stick to legal downloads there is a certain risk involved. There were cases of renowned download portals ...


3

Under the premise that the system is so well-secured that there is only one person which can connect to it via network, then file permissions do not really matter anymore. The operating system can only enforce them against local users anyway. When an attacker can not log into the system or influence some public service running on the machine to do their ...


3

Because mythical imagined malware that might subtly modify your unique proprietary source code is very unlikely to exist, there are a couple of slightly more real threats you could check for. If your friend's computer was compromised by a human hacker, the hacker could have copied your code to his computer, studied it, changed it, and uploaded his changes ...


3

It sounds like your question is really, "How do I harden PHP?" And a second question, "How do I harden Linux to be a web server?" This site is really for extremely specific questions, hence your downvotes. The other reasons for the downvotes, is because since your questions are so broad, there are ample google searches for you to mine to get your ...


2

No - it does not mean you are not vulnerable. The patches you have installed may have fixed the particular vulnerability, but failure of a test does not automatically mean you are safe - it could just be the case that your test version is misconfigured, failed due to a local configuration or bug, or has had some other problem. The usual way to gain ...


2

The only way that I'm aware of for you to prove this "beyond any doubt" would be to have your client audit the servers themselves, or to have them audited by a 3rd party (e.g. consultant) that you both trust to do the work. Network scanning isn't likely to be sufficient on it's own as that wouldn't cover disabling services or the possibility that a firewall ...


2

Do a full scan of the target machine's IP address with Nmap from LAN or Internet: nmap -p- 12.34.56.78 If you've closed all the unused ports, then you'll see that in the scan result. Edit: It would look like this: Starting Nmap 6.40 ( http://nmap.org ) at 2014-03-29 11:26 CET Nmap scan report for abc.com (12.34.56.78) Host is up (0.030s latency). Not ...


2

Here is what I have done, and still do in some specific cases: I use a machine with no swap. In my case, an old Asus EeePC with the famously horrendous proto-SSD; you really do not want to use it for swap space. Instead, I replaced the RAM chip, up to 2 GB. I configure /tmp to be a RAM-based filesystem (search for "tmpfs" in the man page for "mount"). When ...


2

Non-system partition For partitions other than the system partition you can use the following systemd unit: [Unit] Description=Wipe Keys before <target> After=<target> [Service] Type=oneshot ExecStart=/path/to/wipe [Install] WantedBy=<target> <target> is the corresponding target of your desired mode. From the ...


2

The most secure server is the one which is most efficiently maintained. So this would point at the default SSH server (which happens to be OpenSSH): if a security flaw is found in that software, it can be expected that the corresponding patch will be made available within a few hours, and you will get it through the normal Debian update mechanisms (that I ...


2

I'm gonna add this info here without actual intention to answer my own question. The characters that can get injected on the command line while printing some other characters, better know as escape sequences, are defined really good on this site(Thanks F. Hauri, for mentioning it): http://vt100.net/docs/vt100-ug/chapter3.html Under chapter: Reports ...


2

What you are seeing is xterm control sequences. Control sequences are activated when they are seen in output in the terminal; e.g., when you cat a file with bytes that are non-printable ASCII. In your example, the control sequence is ESC Z (bytes 1B 5A) which returns the terminal ID -- as a command in the terminal. You can try it yourself: echo -e ...


2

Short answer: this is the link you're probably looking for (-s specifies SSID). Longer answer: Precomputed 'hash' files are used to accelerate password bruteforce when cracking WPA. They do this by eliminating the need to perform costly transformation of a password into an encryption key; instead somebody already computed such keys for common SSIDs and ...


2

If a machine is hijack by an hostile entity, then the attacker can gain full access to the hardware -- including every drive which is currently plugged in the machine. If the Linux drives are encrypted with a key that the Windows system never sees (which means that if you want to copy files from the Linux to the Windows, you have to do it from Linux, not ...


2

Yes, it is possible to detect unknown keyloggers and other malware, usually through computer forensics (Volatility or EnCase are well-known software for doing that). Keylogger detection, as for viruses and other malwares, can basically be achieved through two methods (I simplify for answer's clarity) : Signature based detection Heuristic based detection ...


2

It is impossible to detect kernel modifications from inside the system. Whatever rootkit detector you use, the rootkit can be programmed to lie to it. If someone controls your kernel, then they control your system, not you, end of story. GMER suffers from that flaw too, it is intrinsic in the operating principle: it only finds rootkits that aren't good at ...


1

(Quick answer, I don't have the time to research all I remember and double-check my facts.) There are multiple things to consider here: USB sticks may carry payload that you do not know is there, e.g. a virus to infect the computer it's plugged in to. Things like BIOSes, network cards, etc. can often be flashed to upgrade the firmware. You could also ...


1

You could try to encrypt the script using standard methods and decode it on the fly by giving the secret key either directly or through a process. But, this would only help against attackers which have no permissions to modify any of your data or the programs you call, which especially means that they have neither root permission nor the same uid as you. And ...


1

If your PC is going to be online at any point (which in all likelihood it will be) then it is recommended to use virus protection. There is plenty of free and light software that will be sufficient. For installation and continuous scanning, try Microsoft Security Essentials


1

If you don't browse, and if you get your games from official places, you can skip the antivirus. If you browse, or if you get your games through illegal download, then it has to be considered like a traditional PC and protected appropriately, from OS to browser level. If you don't use an antivirus, at least the Microsoft Security Essentials and things like ...


1

First of all, it should be noted that virtualization is not a security measure in any way. This is an infrastructure / application technology, and it won't protect you from being compromised. Generally speaking, using chmod 777 to address application issues (log writing, cache etc.) is not a viable solution. You might want to understand what is going wrong ...


1

There is a Linux version of Skype however, I wouldn't recommend running it on bare metal. Have you considered running a virtual machine on your main Linux system (either Windows or Linux) and running Skype inside that? This way the software inside the virtual machine cannot access the ram of the host. I assume that in such a case the RAM is still ...


1

In addition, I would add that most attackers don't directly log in via the console or ssh, but instead use bugs in other software in order to break out into a root shell or elevate their privileges. Adding 2-factor authentication or other mechanisms will definitely improve your security posture, but must be viewed as part of a larger overall hardening ...



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