Category: SIEM (Page 1 of 5)

Alienvault: Working with Decoders and Rules

When we started out with Alienvault years ago, they were just a smallish, start up company and we worked directly almost with the engineers and sales team in Cork. Of course, a lot has changed since AT&T took over, but during the early days, there were a lot of knowledge and mindshare done directly between us and them. So much so that if you were to check their partner site, they still list us as the only Malaysian company as their reseller, due to the early days of listing. What attracted us to the product was that we could lift the hood and see what was underneath. Alienvault (or OSSIM) was previously a hodgepodge of many working parts that were glued together and somehow made to work. The agent was a product called OSSEC, which is an open-source HIDS. The IDS is Suricata/Snort and if you look closely at the availability tool, you would see the backend is a Nagios running. NFSen is used for their netflow data display, and PRADS for their asset discovery. OPENVAS is their vulnerability scanner and best of all, they allow you to jailbreak the system and go into the OS itself and do what you need to do. In fact, most of the time, we are more comfortable on the command line than through the actual UI itself.

The history aside, the downside of adding in these different applications and getting them all to play nice together, is that you would have to understand the interworkings of these pieces.

For instance, if you were to send logs via Syslog to Alienvault, you would have to know that the daemon rsyslog (not an Alienvault product) is the one being used to receive these logs. If you were to use the agent, then the application receiving these logs is different – it’s the OSSEC server that receives it. So it depends how logs come in, and from there you can decide what you wish to do with it.

The challenge is oftentimes to filter and ‘massage’ the logs when it hits Alienvault. There are a few approaches to this:

The basics are at stage 1 where the client (server, workstation etc) send logs (or have logs to be collected) to Alienvault. The initial filtering should theoretically happen here if possible. Many applications have the capability to control their logs – Windows server being one of them. Turning on debug logs on Linux for instance would cause a fair bit of log traffic across the network. Applications as well, have options of what to log and what not to log. We see firewalls logging traffic logs, proxies logging every single connection that goes through – this causes loads of logs hitting the Alienvault.

AV (especially the All In Ones) isn’t designed to take on heavy loads the way Splunk or other enterprise SIEM like ArcSight, that chews through 100,000 EPS like Galactus chews through planets. The AV approach has always been, we aren’t a SIEM only, we are a unified security management system, so security logs are what we are after. Correlation is what we are after. APT are what we are after. Their philosophy isn’t to overload and do generic Business Intelligence with millions of log lines, but to focus on Security and what is happening to your network. That being said, it’s no pushover as well, being able to work with 90 – 120 million events and going through 15,000 EPS on their enterprise.

The reality however is that most clients just turn on logs at Item 1 and plow these logs over to Alienvault. So it’s really up to Alienvault to start filtering these logs and stopping them coming in. At layer 2, is what we call the outer layer. This is the front line defence against these attacks of logs. These are where the engine running these log systems (OSSEC, rsyslog etc) can filter out and then trickle what is needed to Alienvault main engine itself in Layer 3. The AV main engine also has its form of defence, in policies, where we can create ‘junk’ policies to simply ignore logs coming in and not process them through the resource intensive risk assessment calculations.

So, we are going to assume that Layer 1 filtering wasn’t done. What we are going to look at is sorting out Layer 2 and we will assume that logs are coming in via OSSEC. We will have another article on Rsyslog filtering because that is a whole different novel to write.

When it hits OSSEC, it’s going via default port 1514/udp. Now remember, when logs first enters Alienvault, it doesn’t immediately go into the SIEM event display. It first needs to be logged, before it can be turned into events, before it can trigger alarms. So the basic rule is to get it logged:

Make sure you are receiving logs first.

This may seem juvenile in terms of understanding but we have been through enough to know that no matter WHAT the client says, oftentimes, their systems are not even sending the logs to us! A simple tcpdump -Xni eth0 “udp port 1514” will see if the logs are getting in, so go ahead with that first to ensure you are receiving. Just add a “and host <ip address>” if you need to filter it by the IP address.

Another way that Alienvault allows, when you are getting logs via HIDS/OSSEC is by enabling the “logall” on USM HIDS configuration, which we covered in the previous articles here. But be aware turning on logall potentially will bring a lot of logs and information into the box so we generally avoid this unless it’s really needed.

Once you are seeing logs coming into Alienvault, for OSSEC at least the next thing to do is to move these logs to “alerts.log” and from there, Alienvault can start putting it into the SIEM display.

For this to happen, you need to understand 3 things here, aside from the fact that we are currently now working on layer 2 from the diagram above – OSSEC:

a) Decoders

b) Rules

c) /var/ossec/bin/ossec-logtest

The above are actually OSSEC terminologies – not strictly Alienvault. What this means is that if you were to decouple OSSEC from Alienvault, you can. You can just download OSSEC. Or you could download other products like Wazuh, which is also another product we carry. Wazuh runs OSSEC (its own flavor) but has a different presentation layer (Layer 3 in our diagram above) and integrates with ELK to provide a more enterprise ready product but the foundation came from the same OSSEC principles. So when we talk about Rules and Decoders and using the ossec-logtest script to test your stuff, it’s not an Alienvault specific talk. Alienvault specific talk we can go later with plugins and stuff. In the actual ACSE course from Alienvault (at least the one I passed 5 years ago), there is really no mention on decoders and rules – it basically just focus on the core Alienvault items only.

At this point, we need to make the decision on whether to have the filtering done on OSSEC level (2) or on Alienvault level (3)? As a rule, the closer the filtering is done to source, the better…however, in our opinion, the filtering by Alienvault plugins is a lot more flexible and intuitive in design, compared to OSSEC (and because we are biasedly trained in Alienvault, but not so much in OSSEC). So for this article (which is taking VERY long in getting to its point), we are tasked to simply funnel the logs into /var/ossec/logs/alerts/alerts.log because that is where OSSEC sends its logs to and where we can get our AV plugins to read from.

The logs in /var/ossec/logs/archives/archives.log (remember, we turned on the logall option in the OSSEC configuration for this illustration) aren’t monitored by plugins. Because in a production environment, you won’t have that turned on. So, once you have logs into the alerts.log file, you are good to go, because then you can sit down and write plugins for Alienvault to use in the SIEM display.

OK – Firstly Decoders. OSSEC has a bunch of default decoders (like plugins in Alienvault) that is able to interpret a whole bunch of logs coming in. Basically, the decoder is set up with Regular expression to go through a particular file and just grab the information from the file and drop it into fields like IP address, date, source IPs etc. Similar to the AV plugin, but for this illustration, we are not going to use much of the OSSEC filtering, but simply to ensure we select the right logs and send them over to the alerts.log file.

So ok, let’s take the previous article example of having MySQL logs into Alienvault. Let’s say we have this example query log coming into our Alienvault (archive.log, if we turned it on)

2021 Feb 21 00:46:05 (Host-192-168-1-62) 192.168.1.62->\MySQLLOG/db.log 2021-02-22T09:41:42.271529Z        28 Query     SHOW CREATE TABLE db.persons

So the above doesn’t really offer much, but you can technically see there is the date and time, and the command line etc and a decoder will need to be created to parse the incoming log.

Picking up from where we left off at the Alienvault link, Task 4 covers the steps to create the decoder:

a) Edit /var/ossec/alienvault/decoders/local_decoder.xml and add in the following:

<decoder name="mysql-query">
        <prematch> Query</prematch>
</decoder>
<decoder name="mysql-connect">
        <prematch> Connect\s*</prematch>
</decoder>
<decoder name="mysql-quit">
        <prematch> Quit</prematch>
</decoder>

The above is simplistic decoder to catch the 3 important events from the logs coming in from MySQL – Query log, i.e

2021-02-22T09:41:42.271529Z        28 Query     SHOW CREATE TABLE db.persons

Connect Log

2021-02-20T16:35:28.019734Z        8 Connect   root@localhost on  using SSL/TLS

Quit

2021-02-20T18:29:35.626687Z       13 Quit  

Now of course, for those aware, the Query logs have many different types of query – Query Use, Query Show, Query Select, Query Set, Query Insert, Query Update and so on. The idea of the decoder is simply to catch all the queries, and we will theoretically log all Queries into Alienvault.

Now, remember to tell Alienvault you have a new decoder file

In the USM Appliance web UI, go to Environment > Detection > HIDS > Config > Configuration.

Add <decoder>alienvault/decoders/local_decoder.xml</decoder> after <decoder> :

Adding the "local_decoder.xmll" setting to ossec_config

Adding this setting enables the usage of a custom decoder. Save it and restart HIDS.

So that’s it for the decoder.

Now, on the CLI, go to /var/ossec/bin and run ./ossec-logtest

Paste the following “2021-02-20T18:29:43.189931Z 15 Query SET NAMES utf8mb4”

And you should the get result as below

linux:/var/ossec/bin# ./ossec-logtest
2021/03/29 09:50:10 ossec-testrule: INFO: Reading decoder file alienvault/decoders/decoder.xml.
2021/03/29 09:50:10 ossec-testrule: INFO: Reading decoder file alienvault/decoders/local_decoder.xml.
2021/03/29 09:50:10 ossec-testrule: INFO: Started (pid: 25070).
ossec-testrule: Type one log per line.
2021-02-20T18:29:43.189931Z 15 Query SET NAMES utf8mb4
**Phase 1: Completed pre-decoding.
full event: '2021-02-20T18:29:43.189931Z 15 Query SET NAMES utf8mb4'
hostname: 'linux'
program_name: '(null)'
log: '2021-02-20T18:29:43.189931Z 15 Query SET NAMES utf8mb4'
**Phase 2: Completed decoding.
decoder: 'mysql-query'

So basically, any logs that come into archive.log that has that sample line “Query” you will be lumping it in as mysql-query decoded. Of course you can further refine it with Regular expression to get the exact term you wish, but for the illustration, we want to catch the queries here and it’s fine for now.

The next item is the rules. Again, referring to the Alienvault writeup above, go ahead and edit
/var/ossec/alienvault/rules/local_rules.xml.

What we will do is to add the following in

<group name="mysql-connect">
<rule id="192000" level="0">
<decoded_as>mysql-connect</decoded_as>
<description>Connect log is enabled</description>
</rule>

<rule id="192001" level="1">
<if_sid>192000</if_sid>
<regex>Connect\s*</regex>
<description>Connection is found</description>
</rule>
</group>


<group name="mysql-query">
<rule id="195000" level="0">
<decoded_as>mysql-query</decoded_as>
<description>Mysql Query log is enabled!</description>
</rule>


<rule id="195001" level="0">
<if_sid>195000</if_sid>
<match>SET</match>
<description>Query set is found and ignored!</description>
</rule>


<rule id="195002" level="1">
<if_sid>195000</if_sid>
<regex>Query\s*</regex>
<description>Query is found</description>
</rule>
</group>


<group name="mysql-quit">
<rule id="194000" level="0">
<decoded_as>mysql-quit</decoded_as>
<description> Quit log is enabled</description>
</rule>

<rule id="194001" level="1">
<if_sid>194000</if_sid>
<regex>Quit\s*</regex>
<description>Quit command is found</description>
</rule>
</group>

So what the above does is to decide what to do with 3 types of MySQL logs you are getting: Connect, Query and Quit. We want to dump these logs into alerts.log so that we can work on it with Alienvault’s plugin. We don’t want to do any fancy stuff here so it’s pretty straightforward.

Each of these 3 have a foundation rule

a) Connect – 192000

b) Quit – 194000

c) Query – 195000

Each rule has a nested rule to decide what to do with it. Notice you can actually do Regex or Match on the rules which really provides a lot of flexibility in filtering. In fact, if it wasn’t for Alienvault’s plugins, OSSEC’s filtering would probably be sufficient for most of your custom logs requirement.

For this illustration, our job is simple – for each of these rules, find out the key word in the log, and then escalate it to an alert. An alert is created when you create a rule ID with level = 1, i.e <rule id=”195002″ level=”1″>

If you run ossec-logtest again, and paste the log there, you would be able to see

**Phase 1: Completed pre-decoding.
full event: '2021 Feb 21 00:46:46 (Host-192-168-1-62) 192.168.1.62->\MySQLLOG/db.log 2021-02-22T09:42:21.711131Z 28 Quit'
hostname: '(Host-192-168-1-62)'
program_name: '(null)'
log: '192.168.1.62->\MySQLLOG/db.log 2021-02-22T09:42:21.711131Z 28 Quit'
**Phase 2: Completed decoding.
decoder: 'mysql-quit'
**Phase 3: Completed filtering (rules).
Rule id: '194001'
Level: '1'
Description: 'Quit command is found'
**Alert to be generated.

Once you see “alert to be generated” you will find that same alert in the /var/ossec/logs/alerts/alerts.log

AV - Alert - "1613881201" --> RID: "197011"; RL: "1"; RG: "connect"; RC: "Quit Command found"; USER: "None"; SRCIP: "None"; HOSTNAME: "(Host-192-168-1-62) 192.168.1.62->\MySQLLOG/db.log"; LOCATION: "(Host-192-168-1-62) 192.168.1.62->\MySQLLOG/db.log"; EVENT: "[INIT] 2021-02-22T09:42:21.711131Z        28 Quit       [END]";

From there, you can go about doing the plugins and getting it into the SIEM.

Whew. That’s it.

You would notice, however, there is another sub-rules in there for Query:

<rule id="195001" level="0">
<if_sid>195000</if_sid>
<match>SET</match>
<description>Query set is found and ignored!</description>
</rule>

This is set above the “alert” rule and you notice that this is Level=0. This means whatever Query that is decoded, first runs this rule and basically if I see there is a Query “SET”, I am going to ignore it. I.e it’s not a log I want and I am not going to put it into the alerts.log. Level 0 means, not to alert.

I am ignoring Query Set because in this case, we are finding millions of query set as it is invoked a lot of times and mostly it is false positives. I am interested in Query Selects, Inserts and Updates etc.

Once you have this rule put in, it will filter out all Query Sets. This is basically the only filtering we are doing so we don’t have those millions of Query Sets jamming up my alerts.log file in Alienvault.

alienvault:/var/ossec/logs/archives# ossec-logtest
2021/03/14 12:36:33 ossec-testrule: INFO: Reading decoder file alienvault/decoders/decoder.xml.
2021/03/14 12:36:33 ossec-testrule: INFO: Reading decoder file alienvault/decoders/local_decoder.xml.
2021/03/14 12:36:33 ossec-testrule: INFO: Started (pid: 12550).
ossec-testrule: Type one log per line.
192.168.1.62->\MySQLLOG/db.log 2021-03-14T16:22:58.573134Z 19 Query SET NAMES utf8mb4'
**Phase 1: Completed pre-decoding.
full event: '192.168.1.62->\MySQLLOG/db.log 2021-03-14T16:22:58.573134Z 19 Query SET NAMES utf8mb4''
hostname: 'alienvault'
program_name: '(null)'
log: '192.168.1.62->\MySQLLOG/db.log 2021-03-14T16:22:58.573134Z 19 Query SET NAMES utf8mb4''
**Phase 2: Completed decoding.
decoder: 'mysql-query'
**Phase 3: Completed filtering (rules).
Rule id: '195001'
Level: '0'
Description: 'Query set is found and ignored!'

So you see, from the above, all Query Sets are ignored. You can basically do whatever you wish by using either Regex or Match and ignore certain log messages from OSSEC itself. It’s very powerful and flexible and with enough time and effort, you can really filter out only the needed logs you want into Alienvault, which is really part of the fine-tuning process for SIEM.

So there you have it. What you have done now is to take those logs from archives.log and make sure you only put the logs you want in alerts.log (Quit, Connect, All Query except for Query Set).

The next thing you need to do is to go down to Alienvault (layer 3) and do the heavy lifting in writing plugins and get these events into the SIEM display.

For more information for Alienvault and how it can help your compliance, send us an email at alienvault@pkfmalaysia.com and we will get back to you ASAP!

Getting MySQL logs into Alienvault

So from our previous article we have gotten Alienvault (or OSSIM) running in your own Virtualbox, and it is able to communicate with the host (your laptop). Again, the reason why we have this is for a small mini lab that you can just shoot up without worrying about doing a VPN connectivity back to the office or whereever, and just do a very basic troubleshooting or learning. It’s highly useful for us, especially we deal a lot with custom applications plugins where we need to either filter or interpret using Alienvault.

So the objective here is to first get MySQL installed and running, and then have MySQL start logging. Now, for the sake of standardisation, we are going to install MySQL Community Edition. Instead of detailing all the complexity of Windows installation, we will keep it brief: Download, click, wait, done.

The more detailed link is as below, but in all honesty, there is nothing overly difficult with clicking on the windows installation file. Locating where you downloaded it is probably a bit more difficult that the actual installation itself.

https://dev.mysql.com/doc/refman/8.0/en/windows-installation.html

Once it’s installed, (we just installed it as a service), verify that its up and running by going to the Windows services and checking for MySQL80. Or you could just run netstat – an and find the following:

TCP 0.0.0.0:3306 0.0.0.0:0 LISTENING

Next, for the sake of laziness, you probably want to add the MySQL Bin path to your windows environmental variable path: C:\Program Files\MySQL\MySQL Shell 8.0\bin\. Just go System Properties ->Advance -> Environmental Variables.

Once that is done, you can run the command

mysql -u username -p

You should be prompted with a password and you can enter that and you should be in.

Now, we are not going to go through mysql CLI commands as this isn’t the point of the article. The point here is to create some sort of logs from MySQL and fetch those logs over to Alienvault. There are many ways to do it, and it seems for windows, the easiest would be to just dump it into the event viewer and let HIDS go and fetch it. But we don’t like to do things the easy way because we are technology sadists. So the idea here is to log MySQL to a flat file and get HIDS to grab it and get Alienvault to interpret it.

Logging and MySQL does have a long history with us. We’ve written an article a few years ago on getting MySQL community edition to log queries using the MariaDB plugin: https://www.pkfavantedge.com/it-compliance/pci-dss-logging-in-mysql-community-version-with-mariadb-plugin/. 

We are a big fan of the above plugin, as most of our clients tend to end up with MySQL Community Edition, which means some plugins like the official MySQL Enterprise Audit Plugin is not available for cheapskate like us. There is the Percona Audit plugin as well which we have not tried but it seems very much focused on Percona. There is also the McAfee plugin which we tried but after a bit of tinkering decided we were probably too stupid busy to make it work. So we were left with the MariaDB plugin which we got it to work for our client.

It’s still a good read but it has been a few years old. And we will definitely relook into it in the near future.

This time around, we are going to get MySQL Windows version to write the general query log into a flat file instead and have HIDS pick it up. This provides us with a few ideas of how HIDS/Alienvault can be configured to pick up any flat file, which gives you pretty much God-like powers in terms of being flexible in getting logs to your Alienvault. If we can get any flat file and create events from those, the possibility to integrate with any custom applications is endless.

To start you need to be aware of two things:

a) There is already a native logging capability in MySQL CE to log to a flat file which we will be using for illustrative purpose: the all powerful “General query” log. Why we say illustrative is that this isn’t probably a long term solution as it’s akin to turning on a debug on your app. There is a LOT of logs, because every query is logged. Useful for troubleshooting, not so cool if you have a busy server because it grows pretty quickly.

b) Windows doesn’t have a native way to send logs, except by way of WEF (Windows Event Forwarder) which basically just sends logs to a collector (windows system). It seems like an awfully clunky way to do log centralisation, so its probably better (still in 2021!) to use either a forwarder like NXLOG or install OSSEC (HIDS) as an agent to talk to Alienvault.

So for this article, we will start by enabling general query log on your Windows MySQL instance.

mysql> set global general_log_file='C:\MySQLLOG\db.log';
Query OK, 0 rows affected (2.39 sec)

mysql> set global log_output = 'file';
Query OK, 0 rows affected (0.00 sec)

mysql> set global general_log = on;
Query OK, 0 rows affected (0.00 sec)

mysql> show variables like '%general%';
+------------------+----------------------------+
| Variable_name | Value |
+------------------+----------------------------+
| general_log | ON |
| general_log_file | C:/MySQLLOG/db.log |
+------------------+----------------------------+
2 rows in set (0.01 sec)

The above series of commands basically just tells MySQL to turn on general log, and then say where the the file is located and instruct it to be a file. You can verify if it is set by the last command.

For more persistence, you can go ahead and and edit C:\ProgramData\MySQL\MySQL Server 8.0\my.ini

And include the following under the header General and Slow Logging

#General and Slow logging.
log-output=FILE
general-log=1
general_log_file="C:/MySQLLOG/db.log"

Restart your service and you should be able to see if there is a db.log file (You can name it anything).

Try to do a login with your mysql console and you should be able to see a “Connect” log and a few query logs in the flat file.

Now, the next thing is to find a way to forward these logs over to Alienvault. So you could use NXLOG (we covered that in detailed in a series here) However, that topic has been beaten to death over that series so we won’t look at that option for now.

Or we could re-explore using the HIDS (OSSEC) to capture the flat file which we started doing in this article https://www.pkfavantedge.com/pkf-avant-edge/alienvault-usm-flat-file-log-capture-part-1/ but for some reason, never finished what we started.

So for the sake of brevity, the Part 1 link should be very straightforward to follow. Install OSSEC HIDS into your laptop (which is also your MySQL server), but of course, change the OSSEC config to reflect the proper path and file of the flat file log of MySQL that you just created here.

So the conclusion of it is this:

a) You have a running MySQL server and you are able to query and log to it. I would suggest at this point to install a MySQL gui like HeidiSQL or PHPMyadmin to interact with your database. If you are fine with Workbench or CLI, then go ahead. For me, I like HeidiSQL because its clean, and very useful for simple testing and querying.

b) Your MySQL is logging into a flatfile of your choosing, every single log. Again, since this is a test, it’s fine. For a live server, be aware to have a cleanup script in place to ensure your general query log doesn’t over grow.

c) You have HIDS (OSSEC) – we use both interchangeably, so you know – installed on your laptop server, and it’s configured to pick up the logs from the flat file of MySQL that you have configured

d) On the OSSIM (Alienvault) – we use both interchangeably, so you know – on your Virtualbox, you have enabled HIDS to logall so the raw log is now dumped into archives.log (which we would recommend to remove the logall directive once we finish configuring, since this file will also grow quickly on live environment).

At this point, if you were to open up the
/var/ossec/logs/archives/archives.log of your Alienvault, you would observe that the format of the log coming in is

2021 Feb 22 09:41:42 (Host-192-168-1-111) 192.168.1.111->\MySQLLOG/db.log 2021-02-22T09:41:42.271529Z        28 Query     SHOW CREATE TABLE dbtest.persons

Compared to the log from the database file itself

 2021-02-22T09:41:42.271529Z         28 Query SHOW  
CREATE TABLE dbtest.persons

So it is actually word for word, the actual log itself. That’s great but aside from centralisation, it’s actually not doing anything (sort of like Batman in Justice League). It’s just there, with no purpose.

In our next article (which we will call Flat file log capture part 2), we will break down the structure in which logs flow into Alienvault and how ultimately we can get these logs to eventually be seen in the SIEM event.

Meantime, feel free to drop us an email for any SIEM/Alienvault matters at alienvault@pkfmalaysia.com.

Alienvault via VirtualBox

Ok, it’s been a while since we last written anything close to being technical, so let’s quickly get to it.

Many times, we would like to get some quick testing done on an Alienvault box but we don’t have any at hand. Some of these tests are for example, to validate a plugin you just wrote, or to check on a config that you would want to implement for your client but don’t want to test it there. There are many scenarios where you’d just want to fire up a simple box and do some testing. One way is to set up an Alienvault in your office and a couple of servers to run as test systems. A simple VPN in and voila, you are done. But what if you wanted to simulate logs, but don’t have the necessary systems to do so, or rather not change any production systems you have at hand?

One way is to install Alienvault on virtualbox on your laptop, and either simulate logs from other VMs to it, or just get your host laptop to send the guest Alienvault logs. Virtualbox is probably the easiest way to get it done. You don’t need to set it up as an extremely powerful system, since mostly you would be doing testing on it. For me, simply using it for plugin verification, decoder, rules set up and simple log testing was enough. I set the VM up for 2 processors, 8GB RAM, 30GB storage (fixed) and downloaded the OSSIM image to set it up.

To further simplify, we followed this excellent tutorial here. Kudos to the writer for the details. So the idea was two fold, to get our host talking to OSSIM and for OSSIM to be able to go to the internet. The trickiest part of this relatively simple setup is to get the networking sorted.

OSSIM allows two interfaces to be setup in theory – whereby one is used for management interface and the other for log collections. The slight difference here is that I’ve set up the eth0 as ‘bridged adapter’ and selected my laptop’s wireless adapter, and in theory this should allow internet access as required. The second adapter in theory, wouldn’t really be needed, as it’s generally used if you are accessing it from internally (let’s say you set up Virtualbox in a separate box and you access it from an internal network). But because I am building it all in one (everything in a single laptop), I don’t need that second interface as I can just access my management interface through my logging interface. So go ahead and just set up eth0 as bridge and later on, assign the IP to be the same network as your laptop’s network.

The strange thing you may experience from time to time is that you may not be able to SSH into your OSSIM for some reason. It could be an IP conflict or your ARP needs to be updated, especially if you have other systems with the same IP. So you could try just pinging from the server to the host, and host to the server and that may resolve that issue.

Now you are done, go ahead and access your OSSIM. In our next article, we can start a very simple tutorial of setting up a MYSQL database (also within the same laptop), writing a log file to a file and getting Alienvault to pick up the log file via HIDS.

Alienvault USM Anywhere Updates

We just received very good updates from the Alienvault channel team (or AT&T Cybersecurity team as they call themselves now). I think to quickly summarise our excitement into two short phrases:

a) Google Cloud Support – Heck Yeah.

b) Custom Plugin Development – Heck Yeah!

Of course, there were tons of other updates as well, such as scheduled reports, unified UI, more AlienApps support, Cloudflare integration (which is very interesting, as we can identify actions to it, effectively making Alienvault function more like an active prevention system, as opposed to its traditional detective role), new search capability incorporating wildcard searches and advanced asset importing through CSVs as opposed to rudely scanning our clients network.

But the two main courses were the Google Native support and custom plugin.

Google Native support has been a pain point for years. We do have customers moving into GCP or already into GCP where we have been constantly battling to match their expectations for Alienvault to perform as seamlessly as it does on AWS – but it can’t. We had to rely on EDR (endpoint detection and response) for instance, where the agent grabs logs a’la HIDS and sends it over to the server directly. Of course, areas where a native sensor would function, such as creating an internal VPC filter mechanism, or doing vulnerability scanning without having too much inter VPC traffic – these were not able to be done with the EDR so it was very much a bandaid. We knew that our patched up GCP solution wasn’t functioning as well as its handsomer and more dashing brother, AWS. In other words, it kinda sucked.

GCP custom applications also presented its own set of issues – custom apps were difficult to integrate – even with Stackdriver, or us logging to BigQuery, presented a lot of issues to send these logs to Alienvault. When we could configure to send to BigQuery, we couldn’t filter properly, causing our 1TB per month customer quota to be annihilated within days. Now, getting PUB/SUB to work with Alienvault requires APIs to be written, and on top of that to have Alienvault write the custom plugins – all these add to pro services costs, and more importantly, resource and time cost to the project.

So what happens now? In the next General Acceptance/Availability of USM-A, GCP will be supported. The information is sparse so more updates will be forthcoming. But the GCP sensor will be able to:

a) Perform threat detection (like all other sensors), asset discovery, provide Alarms, events, widgets, correlation etc. Basically, it will be native to GCP, doing what it is doing for AWS, Azure and on-prem Hyper and VMWare.

b) Detect VPC flow logs

c) Monitor cloud services through Stackdriver

The last bit is very important. Stackdriver, in essence, is GCP’s answer to Cloudwatch and Cloudtrail of AWS. It monitors and manages services, containers, applications and infrastructure for the cloud. If you have a Cloud services or developing cloud applications, you should be able to support Stackdriver logging. In GCP Compute, the logging agent is used to stream logs from VM Instances. It can even provide the traditional network flow logs (or VPC flow logs), which MSPs can use to monitor network health etc. In other words, this ugly GCP little brother solution is going to get buffed. We’re going to look a lot better now.

The roadmap is bright: Automatic response action against a cloud service when a security event occurs – putting Alienvault into more of a proactive than detective stance it takes traditionally. This is similar to what the Cloudflare integration is achieving. More and more GCP services will be added to be supported. There is also a topic on “User Entity Behaviour Analytics” – which is basically matching behaviour to normal baselines and telling us that Bob is having coffee at 10 am instead of his usual 8 am, which meant he was running late to work, which meant he got stuck in traffic, which meant he left the house late, which meant he woke up late, which meant he slept late last night, which meant he went out for a drink with someone and got smashed, which could possibly mean he is having an affair with a stripper named Daisy. Maybe.

So, pretty exciting times, Aliens!

The other one on the plate wasn’t on the normal discussion agenda but was brought up by us on the international call – we just bombarded the screen with around 10 – 15 queries and at least 4 made it to the table. One of them was: when the hell are we going to get to do our own plugins?

No offence to Alienvault, who currently for USM-A are doing our client’s custom plugins – but 3 – 4 weeks isn’t really going to cut it. Furthermore, sometimes we are not even getting what we want from the custom plugins. We don’t blame Alienvault. The application is ours (as in our client’s). We are the ones who know the events, the priorities. We know what we want to see. We just can’t develop the plugins like what we do now for our USM Appliance clients.

Imagine the win-win situation here. We write plugins for clients (assuming its similar to Appliance), within 2 – 3 days we are done. Testing, another 1 – 2 days. Instead of setting the project timeline back 3 – 4 weeks we are 1 week in. That’s a HUGE impact for compliance clients who are often chasing a deadline. 3 weeks squashed to 1? Hell, Yeah! The win is also for Alienvault. They don’t have to deal with nagging customers or smart-ass channel partners like us banging them for not updating us on our new application plugin. Imagine the parties engineers can now attend to instead of writing regex for a company operating in Elbonia. Imagine the time they now can save and spend socialising with the rest of the world, or having the chance to meet people like Daisy.

It’s a whole new world, really.

So, Alienvault, please, get those updates to us as soon as you can and the world will be a better place for it.

If you need any information on Alienvault, or general help on your SIEM or PCI-DSS compliance, drop us an email on alienvault@pkfmalaysia.com and we will attend to it immediately!

Alienvault USM – Flat File Log Capture – Part 1

We’ve been working with and on Alienvault since the beginning of 2016 and a lot has changed since then. When we started out with Alienvault, they were a small-ish company still, with big ambitions, working with a very technical group out of Cork, Ireland. We had direct access to their technical team (I think even to one engineer) and the amount of knowledge we got from those early days are pretty much invaluable to where we are right now. Of course, Alienvault has changed a lot since then, and now being part of AT&T – for the record, we believe they have the right roadmap to go into cloud with their USM Anywhere concept, and their product right now is much more robust and enterprise ready. They are on the right trajectory.

However, back in the days, for Alienvault USM Appliance (not Anywhere), which is their Appliance offering, we could literally ‘jailbreak’ the system and go into the underlying OS and do stuff to Alienvault that we can’t do anymore in Anywhere. Some of the changes we made were to increase optimisation, put in our own scripts to clean up the system, troubleshoot the system and of course, create plugins for custom applications. We would write custom plugins in 1 – 2 days for multiple applications because of deadlines, I remember and had to do so much in so little time – but we did it anyway. We had to write a plugin for one of the oldest mainframes for a financial institution that was so difficult to interpret, we had to dig up old manuals to sort out the entries for log and events. It was like we were interpreting Egyptian hieroglyphs. But that’s what it took – 2 days, I think because of compliance requirements and customer breathing down our neck to get it done.

Writing plugins was the easier part of the battle – in some old machines or legacy applications, getting the logs was the problem. If Alienvault doesn’t get the logs, it can’t do anything with it. One solution was to leverage on the HIDs (Host IDS), or OSSEC as it was known, to grab log files from systems. It wasn’t so elegant, and we still had to end up writing plugins for it to normalise, but it resolve the issue where application was not able to forward logs to the SIEM, or not able to write the logs to the Windows Event service, or any other way to get logs out to a syslogger. So the solution here is for the application to just write the logs to a file, and Alienvault go ahead and grab this and interpret it. It may not be real time, but it works.

There’s a good write up over in Alienvault at
https://www.alienvault.com/documentation/usm-appliance/ids-configuration/process-reading-log-file-with-hids-agent-windows.htm. So a lot of it is just a repeat and probably an exposition on why we are doing certain things in a certain way.

So the first thing to do here is to ensure that you are able to install HIDs on the server. HIDs will be the key to get this file out to Alienvault. Technically, you could actually use NXLog as well but let’s explore that another time.

Once HIDs is installed, get into the ossec configuration file to define the <localfile> location. Now assuming that you have configured your application to write to a flat file called database.log.txt.

Go ahead and restart OSSEC. That’s pretty much what you need to do to start off so it’s pretty simple.

The rest of it is all done on Alienvault.

To summarise the steps:

Enable “logall” on your USM Appliance. You want to dump whatever you are getting in that flat file database log to a log inside your Alienvault so you can start doing stuff to it. In this case, in your AV User Interface:

Environment > Detection > HIDS > Config > Configuration.

Add <logall>yes</logall> to the <global> section of the file .

You are dumping these logs into /var/ossec/logs/archives/archives.log.

Restart the HIDs service through UI.

You should be able to see new logs coming into archives.log. Just do a tail -f on it, edit the log file (database.log.txt) in your remote system (just write something on it) and see if it appears in your archives.log. Once you see it, you are almost done. Very simple.

So for now, you have customised logs coming into your Alienvault. The next thing to do is to interpret these logs and make sure events are able to be derived from these logs to something that is useful to you!

Drop us an email at alienvault@pkfmalaysia.com for more information on Alienvault or any technical queries you have, and we will attend to it.

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