Intrusion Detection System, a system for detecting and alerting based on behavior.

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41 views

What are the technical implmentation differences between signature based scanning and heuristic based scanning?

Signature based scanning works by comparing something to a database. So does this basically amount to scanning file x for string "foobar" ? I know heuristic based scanning can detect new threats that ...
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0answers
15 views

Process of auditd -s enable/disable persists for a long time

I have setup auditd on my system, with some basic rules from CIS Benchmark paper and the following auditd.conf file: log_file = /var/log/audit/audit.log log_format = RAW log_group = root ...
4
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0answers
38 views

Detecting Process Hollowing

I was brainstorming methods of detecting process hollowing and other forms of code injection, and this one seemed pretty robust. Would it be possible for a "process hollowing scanner" to enumerate ...
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1answer
83 views

Raspberry Pi IDS/FireWall - Should I? [closed]

I was excited to setup an IDS/FireWall with my new Raspberry Pi on a standard home network. Reading threats to SSH and Linux, now I am not so sure. Setup by an experienced amateur I'm now concerned ...
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2answers
98 views

How can the nmap tool be used to evade a firewall/IDS?

Some techniques are used to secure the operating system against network attacks e.g.: firewalls, antivirus software, an IDS like SNORT, etc. To take advantage of the nmap tool, is it possible to ...
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0answers
56 views

Explanation for these entries in the Suricata fast.log?

We have installed Suricata on our system. We have the following similar lines in our fast.log. Can anyone explain these lines? 03/17/2016-17:18:52.744707 [**] [1:2200075:1] SURICATA UDPv4 invalid ...
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0answers
58 views

Snort Portscan Preprocessor Analysis

Remarks I really apologize if this content isn't matching the community, but I am not getting approved on snort-mailing lists and I don't know what can I do for the same, therefore I feel this can be ...
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2answers
27 views

Snort Unable to detect portscans in LAN

Setup Information I am doing experiment on portscan detection using snort 2.9.8.I have 10 systems in my lab with id:1,2,3,...,10. i have installed snort in my lab-pc with id:1.Now i am using Pc with ...
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1answer
43 views

Tap-mode IPS vs IDS

It is my understanding that tap mode IPS, unlike in-line mode, is passive and cannot prevent attacks. In that case, what is the difference between an IDS and a tap mode IPS? I've checked out several ...
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0answers
38 views

Inconsistent duplicate TCP packets

How often does it happen that we benignly see a TCP packet that is retransmitted but has a different payload the second time? In other words, how often is it that we see a TCP packet with sequence ...
4
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1answer
62 views

Do generic custom scripts avoid detection more than common security applications?

Are scripts coded only using the default API of a high level, interpreted language for generic and meticulous gathering of network device and host software information that are already available ...
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3answers
73 views

How does a hack leave no trace in server logs when there is a WORM IDS?

I am wondering if a hacker managed to either SQL inject or social engineer into a database, how does one not leave a trace in the IDS (Intrusion detection like OSSEC)? If an IDS is monitoring the ...
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0answers
38 views

Network configuration for Security Onion on VMWare ESX

I'm setting up an IDS using Security Onion on VMWare ESX. I have a VLAN from the (physical) switch which has the network SPAN port; this is feeding into the ESX virtual switch, and this port group is ...
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1answer
84 views

Understand how dionaea honeypot emulated services work

I'm trying to understand Dionaea honeypot and the information flow. I understand that it emulates some services, like SMB, ftp, tftp, try to responde with these, then gets the shellcode and ...
4
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1answer
68 views

Basic question about how an IDS works

Would the location of an Intrusion Detection (or Packet Analysis) sensor on an internal network impact whether the external host's Source IP (assuming inbound TCP traffic) is retrievable from a ...
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4answers
2k views

Detect non HTTP packets using port 80

We are currently doing port whitelisting on our firewalls which is working well but this of course does not prevent the implementation of side channels or the misuse of these ports for other purposes. ...
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0answers
32 views

Is there an easier way to test suricata has enough resources to run without losing packets?

I'd like to see the effect of changing my Suricata hardware and software, and in particular make sure I can determine the rate above which I'll start to lose data. I'm running ESXi with 20 cores and ...
6
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1answer
620 views

How do I identify which PC made a suspicious DNS query?

Our IDS detected a suspicious DNS packet going to a Botnet (or similar). Since that DC is a recursive relay, how can we identify the client who made that request. (Windows DNS server)
2
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1answer
73 views

Linux (!) Network Architecture for CTF-scenario [closed]

My boss recently enrolled me in an InfoSec training. I am part of the network team, but have limited experience in InfoSec. My first assignment is to draw a layout of a network that will be used ...
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2answers
83 views

Distinction of DPI and IDS

I'm currently reading about Intrusion Detection Systems (IDS) and noticed a huge variety of definitions for the term of Deep Packet Inspection. Especially the NIST shows three different techniques in ...
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1answer
132 views

(spp_sdf) SDF Combination Alerts in Snort

I'm testing Snort in IDS mode and have been receiving a few (spp_sdf) SDF Combination Alerts as below. Seems like it happens when I visit certain but not all https sites. Tried to google this alert ...
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1answer
71 views

Are snort rules applied per packet or per flow

I would like to understand if snort rules are applied for each packet in a flow between a source and destination separately? For instance, when packet 1 of the flow arrives at the IDS, all the rules ...
0
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1answer
69 views

snort rule to detect relay attempt not working

I am trying to detect a relay attempt on smtp server, but nothing gets logs when I test it out. The snort rule to detect a relay attempt which I tried using is: alert tcp $SMTP_SERVERS 25 -> ...
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0answers
24 views

Snort matching against single packets

For a specific task, I'd like to match snort rules against the first 1-2 packets of each flow in the network without waiting for the other subsequent flow packets. Can I do this with snort? If so, ...
0
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1answer
69 views

Do I need ossec for my personal home computer? [closed]

Do I really need a HIDS like ossec, or will using good passwords, using a firewall, an antivirus/antimalware program, and a rootkit scanner do the job well enough?
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0answers
141 views

Suricata IPS manual blocking/unblocking vs. snort and guardian

Does anyone have experience with using Suricata as an IPS? Im on Debian and I'd like to be able to manually block and unblock specific ip addresses (iptables). I've not used Suricata as I am currently ...
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1answer
108 views

Which method is the best for IDS : heuristic or signature based? [closed]

In signature based IDS: it maintains a database of the signatures that might signal a particular type of the attack. Problems: New attack that has been specifically constructed in order to not ...
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0answers
18 views

Current Decryption Support for TLS [duplicate]

I've been locking things at clients down recently and ran into a side effect I hadn't really thought about were TLS traffic using DHE based ciphers can't be decrypted with SSLDump or Wireshark. I ...
4
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2answers
371 views

What is the difference between a HIDS/HIPS and an anti virus?

I have gone through what IDS/IPS's are. I understand the difference between a NIDS/NIPS and a HIDS/HIPS. But Host IDS and Host IPS sound like an antivirus software to me, is there a difference?
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1answer
287 views

Is it possible to detect DPI (Deep Packet Inspection)?

If one suspects one's packets are subject to DPI, how can it be detected?
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1answer
562 views

How to detect malicious code sending information to attacker's server in linux

Suppose you have some malicious code on your linux laptop, for example a rootkit or trojan or something like that. Now restrict your attention to the case that the malicious code does transfer some ...
5
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1answer
98 views

Using a single number instead of an IP address or a DNS name, which are concrete uses? [closed]

My question: I have read that using the single number equivalent (called the "binary equivalent" by the author) of the IP address instead of the actual IP address or the domain name can be used "to ...
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0answers
40 views

What kinds of features are useful for network security visualization? [closed]

I just want to know is network security visualization are practical for enterprise network administrators? (Which I am not) And if it is what kind of tools they uses and what kind of features they are ...
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5answers
79k views

Difference between IDS and IPS and Firewall

The differences between an IDS and a firewall are that the latter prevents malicious traffic, whereas the IDS: Passive IDS: the IDS only reports that there was an intrusion. Active IDS: the IDS also ...
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2answers
109 views

How eavesdropping attack takes place in network

I am learning some concepts of network security and I have the following question: One case of eavesdropping attack is that an adversary somehow places himself inside a network to order to capture ...
3
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1answer
7k views

IPS fail close vs IPS fail open, what are the risks and benefits?

If a desicion is to be be made on selecting a mode of fail for an inline IPS that is protecting servers, what are the criteria that should be considored for selecting one of the failure modes: 1- ...
4
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1answer
293 views

Anomaly intrusion detection

Anyone know which opensource network IDSs are using anomaly techniques? My project is to compare them, so if you could give me some hints, that would be much appreciated. Currently, I am looking at ...
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3answers
96 views

Multiple SSL Inspection

I want to ask you if you think that doing SSL Inspection in proxy mode (Resign) could be a problem. The scenario is the following: 1 --> 2 --> 3 Client web browsing IPS device with SSL ...
3
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1answer
68 views

How to make Snort not log sensitive data from the sniffed traffic?

I have Snort in my network which I use for IDS and it is residing on a VM that receives all mirrored traffic from the switch. I am having a web applications that users use and they login, operate on ...
3
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1answer
86 views

Detecting botnets that use HTTP instead of IRC

I know most bots use either IRC or HTTP to communicate with the C&C, and http unlike IRC can't be blocked. So if a botnet is using HTTP, how can this be prevented? Just theoretical!
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0answers
80 views

Snort arpspoof preprocessor not giving alerts

I'm attempting to use Snort to detect a simple arpspoof attack on a test network I've set up. I have the following 4 ip addresses on this network. 192.168.1.1 Router 00:18:39:EC:F5:78 192.168.1.2 ...
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1answer
176 views

Suricata rule to block particular website question

I am writing rule for suricata which is going to block the possibility to enter one of the website for example xyz.com (instead of facebook, because with facebook there are some problems). I am doing ...
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0answers
65 views

Snort rule to detect More Fragments fragbit not working

I have a Virtualbox setup with Snort running on a Windows 7 host and Kali Linux as the attacking machine, connected on an internal network. I'm investigating ways to get Snort to detect fragmentation ...
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0answers
75 views

Is EasyIDS obsolete?

I have found EasyIDS from Skynet Development recently but noticed that the latest change-log is from 2009. Does this mean it is obsolete and should not be used as it is not being kept up-to date?
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0answers
80 views

Switching from Snort rules to Emerging Threats. Is there a way to know which ET rule sid covers the same vulnerabilty as Snort rule sid?

Our company has been using the snort community rules and we have tuned our rule files over years to our specific needs. Now our company has decided to use Emerging Threats (ET) open rules. The ET ...
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2answers
3k views

What are the difference between IPS and WAF in terms of DDoS?

I have heard about both Web Application Firewalls (WAF) and Intrusion Prevention Systems (IPS). Which is better in preventing a Distributed Denial of Service (DDoS) attack and why?
0
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1answer
76 views

fwsnort - How safe compared with Snort/Suricata

How safe is 'fwsnort' compared to a real Snort / Suricata instance? Whats the percentage of VRT / ET Rules, that fwsnort can actually use? I read somewhere from an older article its only ~ 60% - is ...
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0answers
11 views

Adding Windows 7 VM as a log source/forcing the IDS inline

I'm investigating ways to add my Windows 7 VM as a log source or even run that traffic through my IDS VM and then out to the internet but I'm not entirely sure how to approach it. Does anybody have ...
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1answer
17 views

IDS device behaviour

Which of the following is a reasonable response from the ids when its detects ip packets where ip source address and port is the same as the destination IP address and port A. Allow the packet to be ...
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0answers
13 views

get session data (stream data) into Snort ids [closed]

Can any one point to me where (in the code) Snort are stored just before they send to httprespect or got written to the output files? Thanks.