236
votes
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How are anti viruses so fast?
Disclosure: I work for an anti-virus vendor.
Because most anti-virus engines were born as protecting endpoints, and even now for many of them endpoint protection is major part of business, the modern ...
- 3,514
213
votes
Has it been mathematically proven that antivirus can't detect all viruses?
Under one possible interpretation of that, it's a result of Rice's theorem. A program is malicious if it performs some malicious action, which makes it a semantic property. Some programs are malicious ...
200
votes
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Company claims hardwire connections are a security issue
Warning: Conjecture, because none of us know their actual setup.
It is very likely that the organization has their own network, which is hard-wired, as well as a guest network, which is wireless-only....
- 72.6k
194
votes
Has it been mathematically proven that antivirus can't detect all viruses?
Actually, the opposite can be easily proved: since all computer viruses are executable code in one way or another, all you have to do is write an antivirus program that will report ANY executable code ...
- 1,775
177
votes
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Help! My home PC has been infected by a virus! What do I do now?
What do I do now? How do I get rid of the virus?
The best option is what is referred to as "nuke it from orbit." The reference is from Aliens:
The idea behind this is that you wipe your ...
- 7,617
164
votes
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What is the safest way to deal with loads of incoming PDF files, some of which could potentially be malicious?
I think the safest option for you would be to use Qubes OS with its built in DisposableVMs functionality, and its “Convert to Trusted PDF” tool.
What is Qubes OS?
Qubes is an operating system where ...
136
votes
I'm a White Hat and I develop my own viruses. Should I report it when almost all scanners say the executable is safe?
That's a pointless exercise.
Most malware scanners match on fragments of binary code (aka virus signatures), and they check MD5 hashes of known infected code against their blacklists. Unless the ...
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131
votes
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Alternatives to anti-virus for keeping oneself safe
Antivirus is more dangerous in that it parses complex attacker-controlled data in a highly privileged context. This is a recipe for privilege escalation exploits. As a result, sophisticated attackers ...
- 66.3k
111
votes
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Are there technical differences which make Linux less vulnerable to virus than Windows?
There are several reasons why Windows is so heavily inflated with anti-virus products. (I am pointing to out-of-the-box (OOTB) experiences).
Windows users are, by default, local administrators, so ...
- 3,820
100
votes
Accepted
Replacing Windows 7 security updates with anti-virus?
Nope.
After Microsoft discontinue security updates for a version of Windows there is not a safe way to run that version of Windows.
Some people will promote Virtual Patching where you have a ...
- 2,801
95
votes
Has it been mathematically proven that antivirus can't detect all viruses?
According to Wikipedia:
In 1987, Fred Cohen published a demonstration that there is no algorithm that can perfectly detect all possible viruses.
It also references this paper. That might be the ...
- 1,667
66
votes
Accidentally came across the source code for some malware, what to do?
I'm afraid your compiled binary will differ a lot from the actual malware that can be found in the wild. Different compilers and command-line flags will produce completely different binaries, and the ...
- 12.8k
66
votes
Can anti-virus/virus protection be used to spy on you?
Any software you install on your system can compromise the system and thus affect security and privacy. This can be done either willingly or because of bugs in the software. And this is doubly true ...
- 196k
53
votes
Avast AV could read Firefox saved passwords
Passwords saved by Firefox are not encrypted (they are encrypted but the key can be read out) until you set a master password. I don't think that this is a bug, but every virus could read those ...
- 561
52
votes
How are anti viruses so fast?
The common anti-virus (to my knowledge) use a kinda brute force type method where they get the hash of the file and compare it to thousands of known virus' hash. Is it just they have servers with ...
- 22.7k
45
votes
Are there any known cases of antivirus software intentionally sending false alarms?
I have not seen false alarms, but I have seen an excessive amount of warnings/notifications, with Avast, for example. You could receive warnings about how vulnerable you 'might' be, and how you could ...
- 1,595
40
votes
Are there technical differences which make Linux less vulnerable to virus than Windows?
The reason for this tends to be historical. There is no reason why a modern desktop Linux should be particularly more resistant to malware when compared to a modern Windows desktop.
However there ...
- 62k
38
votes
Replacing Windows 7 security updates with anti-virus?
No, anti-malware is not a replacement for security updates.
Neil Matz summarized the Fortinet's Q2 Global Threat Landscape report for 2017, noticing:
WannaCry and NotPetya targeted a vulnerability ...
- 18.4k
37
votes
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Norton detects intrusion attempt from virtual machine - how is this possible?
You are assuming that the intrusion is coming from the VM to the hypervisor. A VM "breakout" is when the VM accesses the host directly.
An infected VM that has access to the network can ...
- 127k
35
votes
Accepted
Are there any known cases of antivirus software intentionally sending false alarms?
The problem with deliberately triggering false alarms is that users will at some point lose trust in the AV software. The rates of false positives are also an important factor in AV rankings - and ...
- 44.5k
32
votes
Are there technical differences which make Linux less vulnerable to virus than Windows?
I think the most crucial factor for virus infection of desktop Windows system is, definitely, the culture and discipline of software distribution and installation.
While the average Linux user opens ...
- 421
32
votes
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Accidentally came across the source code for some malware, what to do?
should I stick it in my IDE, build it and then send the built version to them
That's not a good option. Unless there's some reason to believe that the malware author and you have a dev environment in ...
- 2,018
32
votes
Help! My home PC has been infected by a virus! What do I do now?
I'm sorry to hear you've got a computer virus. Fortunately, thousands of people deal with virus infections daily, and in most cases, the computer and all data can be restored. By following good online ...
- 33.1k
31
votes
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Metasploit Meterpreter alternatives
Bypassing AV and IPS can be done through meterpreter or any other RAT. Most of the time meterpreter is handy because first it is open source and second it is implemented as a reflective DLL which ...
- 5,571
30
votes
Can a virus infection spread from a PC to a PCB and back to a PC?
It's impractical for a PCB to be a vector for malware storage or attacks, but that's because PCBs don't do anything except route electrical signals between components. The components themselves... ...
- 45.4k
29
votes
Accepted
Is HTML5 vibrate feature a security vulnerability?
A popup was used to show the alert. Does this mean that the popup feature introduces vulnerabilities? Then by that line of reasoning JavaScript is the source of all problems. There are people who ...
- 9,847
29
votes
Accepted
Do Linux systems need antivirus against ransomware?
There are actually multiple parts of the question:
Is Linux affected by malware and especially ransomware?
Do antivirus products exist for Linux?
Do these products help against this threat?
To ...
- 196k
28
votes
Accepted
Can I block viruses from a USB stick by scanning it before opening its folder?
Referring to my answer to this question (before it was migrated):
No, scanning the drive without "opening the folder" isn't a secure way to protect against viruses on the drive. It's very ...
- 759
28
votes
Company claims hardwire connections are a security issue
It really depends on how they have set up their network, so we can only speculate. But I can provide a similar anecdote.
My local library has a wifi that you can log into using your library card. ...
- 58.6k
28
votes
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Is it acceptable to exclude folders in antivirus?
Ah yes, ye olde problem of security tools making a system unusable. My arch nemesis.
when is it acceptable to exclude folders in antivirus, and why?
Short answer:
There's an old adage on this site ...
- 58.6k
Only top scored, non community-wiki answers of a minimum length are eligible