Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [malware]

Malware is any software application which subverts the will of the legitimate owner of a computer, by means of force or subterfuge, with or without personal or monetary gain on the part of the creator.

166
votes
10answers
25k views

Help! My home PC has been infected by a virus! What do I do now?

This is an attempt to ask a canonical question as discussed in this old meta post. The goal is to create something helpful that can be used as a duplicate when non experts ask about virus infections. ...
156
votes
9answers
134k views

How secure are virtual machines really? False sense of security?

I was reading this CompTIA Security+ SYO-201 book, and the author David Prowse claims that: Whichever VM you select, the VM cannot cross the software boundaries set in place. For example, a virus ...
158
votes
10answers
18k views

How do you explain the necessity of “nuke it from orbit” to management and users?

When a machine has been infected with malware, most of us here immediately identify the appropriate action as "nuke it from orbit" - i.e. wipe the system and start over. Unfortunately, this is often ...
64
votes
4answers
63k views

Does a Virtual Machine stop malware from doing harm?

I would like to know if it is safe for the host system of a virtual machine (VM - VirtualBox OSE in my case) to execute malware. Can a virus break out and read or write data from the host system? ...
43
votes
8answers
43k views

Is making a clean install enough to remove potential malware?

Is formatting the disk and reinstalling the system from scratch (to Ubuntu) enough to remove any potential hidden software spyware, keyloggers etc.? Or can something still persist installed in the ...
42
votes
3answers
95k views

Can you get virus just by visiting a website in Chrome?

I've recently read Google Chrome: The End of Drive-By Downloads. Is it true to say that drive-by-downloads are history in Google Chrome? So if I have a link (from a spam email) I can right-click >> ...
26
votes
2answers
2k views

Is there a real possibility of getting malware by “drive-by”?

I know malware can be gotten by downloading and running stuff, but is there a real possibility of just viewing a webpage or clicking a link and getting one? Assuming using only Firefox / Chrome and ...
155
votes
5answers
21k views

How can USB sticks be dangerous?

We all know the story of the USB drive left outside a power plant which was found by a worker and inserted into a computer to see the contents which then allowed a hack to ensue. Here is my question, ...
244
votes
10answers
81k views

How is the “WannaCry” Malware spreading and how should users defend themselves from it?

There's a new strain of attacks which is affecting a lot of systems around the world (including the NHS in the UK and Telefonica in Spain) which is being called "WannaCry" amongst other names. It ...
121
votes
11answers
40k views

Is there any way to safely examine the contents of a USB memory stick?

Suppose I found a USB memory stick lying around, and wanted to examine its contents in an attempt to locate its rightful owner. Considering that USB sticks might actually be something altogether more ...
37
votes
12answers
41k views

How to safely view a malicious PDF?

I have a PDF with important information that may contain malware. What would be the best way to view it?
37
votes
6answers
10k views

Can malware be dangerous even when quarantined?

I am reading a book on network security and when talking about user confusion it writes: "It is not uncommon for a user to be asked security questions such as Is it safe to quarantine this ...
7
votes
2answers
1k views

What are ways I can analyze malware in an infected machine, not just clean it?

I often run into infected devices in my environment and would like to learn more about the specific infections that have gotten in. What are the best tools and techniques I could use to do this? I ...
58
votes
4answers
5k views

What security risks are posed by software vendors deploying SSL Intercepting proxies on user desktops (e.g. Superfish)

There has been quite a bit of concern noted relating to the recent discovery that Lenovo are pre-installing a piece of Adware (Superfish) which has the capability of intercepting SSL traffic from ...
18
votes
7answers
11k views

Finding a specific malware sample for malware analysis purposes

I wish to analyze the changes made by a specific virus. For example, Win32.Sality. Where can I get the sample of this, or other similar, malware for testing?
9
votes
7answers
2k views

Difference between virus and trojan?

To my current understanding: A virus is a program that does not self replicate and relies on the host file being spread. It has malicious intent. A trojan is a program that is run by deceiving the ...
46
votes
4answers
108k views

How to inject executable, malicious code into PDF, JPEG, MP3, etc.?

I wanted to know if its generally possible to inject executable code into files like PDFs or JPEGs etc., or must there be some kind of security hole in the application? And if so, how would one do ...
55
votes
4answers
187k views

Can a PDF file contain a virus?

Could a PDF file contain any type of malware?
59
votes
7answers
7k views

Is it safe to install malware in a VM

Is it safe to install malware in virtual machines? I would like to investigate malware, but I don't want to infect my own computer. Can I install the malware in a VMWare VM, maybe even without ...
21
votes
8answers
4k views

Best practices for handling computer viruses

I realize this question may be quite broad (and hopefully not a violation of the FAQs), but I'm interested in hearing how many of you handle a computer infected with Malware. In a small-to-medium ...
19
votes
5answers
4k views

How is a worm different from a virus?

In spite of various online articles, I'm a bit unclear on the distinction between a "worm" and a "virus". Two related questions-- Is there a useful and clear distinction here or no? If so, what is ...
18
votes
6answers
2k views

Methods of mitigating threats from keyloggers

I am concerned about keyloggers being installed on my system and transmitting sensitive data out of our network. Is there a common method that such malware uses to send its collection back to the ...
15
votes
1answer
2k views

Kaspersky Antivirus “secure connection scan” as broken as Superfish?

I've read a lot about Superfish (and similar ad-ware) lately and I basically understand the vulnerability to MITM attacks. But I'm actually wondering if the "secure connection scan" by Kaspersky ...
32
votes
3answers
7k views

Can malware be transmitted via a USB charger plugged into a wall socket?

I have a smart phone that I often plug into a wall socket for charging via a small adapter that rectifies the AC to DC power and transforms the voltage from line (120V or 240V) to 5 V DC, probably ...
23
votes
6answers
2k views

What are the security implications of people downloading addons, wrongly thinking that they are safe?

I recently learned about a plugin for Firefox called Fire Sheep, which was featured on the Security Now podcast. I downloaded F.S. and began examining it. To my surprise it includes C++ code that must ...
7
votes
4answers
20k views

What does this malicious PHP script do? [closed]

Somebody hacked my site and uploaded this script (template46.php) to my webroot and its content is: <?php $vIIJ30Y = Array('1'=>'F', '0'=>'j', '3'=>'s', '2'=>'l', '5'=>'M', '4'=>'...
9
votes
2answers
3k views

Why should I restrict the content type of files be uploaded to my site?

We are building an application where users can upload resumes in our system for our administrators to download. We are having a debate about restricting the content type of the files that can be ...
2
votes
2answers
230 views

Unambiguous terminology for different kinds of malware?

I noticed in the literatures that there are no exact boundaries for numerous information security terms such as malware, virus, etc. Some people say malware in the umbrella under which viruses, worms, ...
161
votes
14answers
17k views

What is the safest way to deal with loads of incoming PDF files, some of which could potentially be malicious?

As an investigative journalist I receive each day dozens of messages, many of which contain PDF documents. But I'm worried about some of the potentially malicious consequences of blindly opening them ...
90
votes
7answers
51k views

Should I get an antivirus for Ubuntu?

Considering the recent thread regarding anti-virus for the Mac I wonder how many of the arguments put forth are relevant today to Linux systems, specifically Ubuntu. There are no known Ubuntu desktop ...
36
votes
6answers
43k views

How do I safely inspect a suspicious email attachment?

I received a pretty blatantly spammy email to my Gmail account. I'm not really sure how it made it through the spam filters, since it has all of the telltale signs. The FROM field is spoofed as ...
30
votes
3answers
3k views

Are official browser add-ons really safe?

Almost any browser addon/extension that I install on my Chrome or Firefox (be it Firebug, RESTClient, ...) warns me, saying: It [the add-on] can: Access your data on all website Access ...
56
votes
11answers
31k views

Can headphones transmit malware?

Can headphones transmit malware? My friend borrowed my headphones (a pair of Apple EarPods) and plugged them into his Android mobile phone for a few minutes in order to listen to a voice message. ...
17
votes
4answers
2k views

Unknown malware, how to report it and whom to report it to?

I'm a professional Windows system administrator, but I've been caught off-guard (or maybe some malware writer has been very clever) and I caught some unknown malware on my home computer (Windows 7 x64 ...
16
votes
3answers
4k views

Can a guest virtual machine be compromised by a virus on the host machine?

All questions ask about the other way round, ie. can a virtual machine compromise the host. But I'm asking can a virus on the host machine compromise the guest virtual machine?
5
votes
1answer
406 views

Drive-by downloads

I am aware of the problem of drive-by downloads, which happens when one visits a malicious site and a malware is downloaded to the PC. I want to ask that when such a program is downloaded, how does it ...
15
votes
5answers
9k views

Detecting malware-infected USB drives

I'm about to distribute some relatively cheap promotional usb drives to some of my company's clients. I'm fairly confident the company I purchased them from wouldn't intentionally implant malware on ...
1
vote
1answer
5k views

Is This A Hack/Malware/Breach? [duplicate]

Browser alerts about a download with a URL: mapuser?providerid={number}&userid={longcapitalstring} ({number} bytes) It gives me the option to save. This looks incredibly suspicious, but it also ...
26
votes
3answers
4k views

Which security measures does PyPI and similar third-party software repositories take?

PyPI is a third-party software repository for Python packages. Everybody can upload packages to it (see The Python Package Index (PyPI)). How does PyPI prevent people from uploading malware? When I ...
22
votes
4answers
7k views

How is malware distributed within zip files?

Recently it seems there has been a big outbreak of zip files being emailed to people with a .js file containing code that downloads and executes cryptoware. How does the .js actually get executed ...
18
votes
3answers
4k views

Router being infected by malware

If you connect a computer that is infected with malware (the government grade, kernel infecting, extremely persistent, easily spreadable kind) to a router or modem, can the router or modem or its ...
12
votes
3answers
2k views

How do I report new malware?

I have a new piece of malware that isn't detected by current anti-virus vendors. How do I report it to them? I want to do a good turn and help protect as many people as possible. What is the best ...
2
votes
1answer
2k views

what is the difference between dll hijacking and dll injection

I am confused. I would like to know if dll hijacking and dll injection are the same or are they different. I know that some malware use it to do malicious things. thank you in advance
8
votes
3answers
13k views

Javascript Malware: How does it work, and how can it be mitigated?

I am wondering how malware gets served through Javascript. I've noticed a few illegitimate pop-ups while visiting some financial websites. I wonder how malware exploits work against the application ...
2
votes
2answers
896 views

SafeZone: keyloggers/malware/spyware protection

As part of Avast free updates you have a chance to use SafeZone browser. Among features of SafeZone browser I found that SafeZone protects you from keyloggers/malware/spyware. I'm interesting ...
110
votes
9answers
18k views

Alternatives to anti-virus for keeping oneself safe

I have read a lot of articles that talk about how using an AV is less safe than not having one for more intermediate PC users who are careful with what they click and download. For example, here are ...
22
votes
4answers
6k views

Malwares source repositories. Where? [closed]

As the best way to learn is to read the code, do you know where I can find malware/virus/whatever source code to read?
29
votes
6answers
14k views

How can normal files hide a virus?

How can normal files supported in the Windows operating system hide a virus? Sometimes opening a .txt , .jpg or .docx files leads to running a virus. How is this possible?
31
votes
6answers
6k views

How safe are employee laptops in China against International corporate espionage?

I recently took a business trip to China. Our IT department told me I could not take my normal machine, and instead gave me a loaner. This loaner had MS Outlook and was linked to my normal company e-...
26
votes
5answers
8k views

How can I safely check whether an email link leads to a malicious website?

Over the last few weeks, I've gotten several spam emails from different friends that only contained links to different websites. I would like to click on those links and see what's on the website. ...