Alert Module¶
Energy Logserver allows you to create alerts, i.e. monitoring queries. These are constant queries that run in the background and when the conditions specified in the alert are met, the specify action is taken.
For example, if you want to know when more than 20 „status:500” responscode from on our homepage appear within an one hour, then we create an alert that check the number of occurrences of the „status:500” query for a specific index every 5 minutes. If the condition we are interested in is met, we send an action in the form of sending a message to our e-mail address. In the action, you can also set the launch of any script.
Enabling the Alert Module¶
To enabling the alert module you should:
- generate writeback index for Alert service:
Only applies to versions 6.1.5 and older. From version 6.1.6 and later, the Alert index is created automatically
/opt/alert/bin/elastalert-create-index --config /opt/alert/config.yaml
- configure the index pattern for alert*
start the Alert service:
systemctl start alert
Creating Alerts¶
To create the alert, click the “Alerts” button from the main menu bar.
We will display a page with tree tabs: Create new alerts in „Create alert rule”, manage alerts in „Alert rules List” and check alert status „Alert Status”.
In the alert creation windows we have an alert creation form:
- Name - the name of the alert, after which we will recognize and search for it.
- Index pattern - a pattern of indexes after which the alert will be searched.
- Role - the role of the user for whom an alert will be available
- Type - type of alert
- Description - description of the alert.
- Example - an example of using a given type of alert. Descriptive field
- Alert method - the action the alert will take if the conditions are met (sending an email message or executing a command)
- Any - additional descriptive field.# List of Alert rules #
The “Alert Rule List” tab contain complete list of previously created alert rules:
In this window, you can activate / deactivate, delete and update alerts
by clicking on the selected icon with the given alert: 
.
Alerts status¶
In the “Alert status” tab, you can check the current alert status: if it activated, when it started and when it ended, how long it lasted, how many event sit found and how many times it worked.
Also, on this tab, you can recover the alert dashboard, by clicking the “Recovery Alert Dashboard” button.# Type of the Alert module rules #
The various RuleType classes, defined in Energy Logserver-Log-Aalytics. An instance is held in memory for each rule, passed all of the data returned by querying Elasticsearch with a given filter, and generates matches based on that data.
- Any - The any rule will match everything. Every hit that the query returns will generate an alert.
- Blacklist - The blacklist rule will check a certain field against a blacklist, and match if it is in the blacklist.
- Whitelist - Similar to blacklist, this rule will compare a certain field to a whitelist, and match if the list does not contain the term.
- Change - This rule will monitor a certain field and match if that field changes.
- Frequency - his rule matches when there are at least a certain number of events in a given time frame.
- Spike - This rule matches when the volume of events during a given time period is spike_height times larger or smaller than during the previous time period.
- Flatline - This rule matches when the total number of events is under a given threshold for a time period.
- New Term - This rule matches when a new value appears in a field that has never been seen before.
- Cardinality - This rule matches when a the total number of unique values for a certain field within a time frame is higher or lower than a threshold.
- Metric Aggregation - This rule matches when the value of a metric within the calculation window is higher or lower than a threshold.
- Percentage Match - This rule matches when the percentage of document in the match bucket within a calculation window is higher or lower than a threshold.
- Unique Long Term - This rule matches when there are values of compare_key in each checked timeframe.
- Find Match - Rule match when in defined period of time, two correlated documents match certain strings.
- Difference - Rule matches for value difference between two aggregations calculated for different periods in time.
- ConsecutiveGrowth - Rule matches for value difference between two aggregations calculated for different periods in time.
Example of rules¶
Unix - Authentication Fail¶
index pattern:
syslog-*
Type:
FrequencyAlert Method:
EmailAny:
num_events: 4 timeframe: minutes: 5 filter: - query_string: query: "program: (ssh OR sshd OR su OR sudo) AND message: \"Failed password\""
Windows - Firewall disable or modify¶
index pattern:
beats-*
Type:
AnyAlert Method:
EmailAny:
filter:
- query_string:
query: "event_id:(4947 OR 4948 OR 4946 OR 4949 OR 4954 OR 4956 OR 5025)"
SIEM Rules¶
Beginning with version 6.1.7, the following SIEM rules are delivered with the product.
| Nr. | Architecture/Application | Rule Name | Description | Index name | Requirements | Source | Time definition | Threashold |
|-----|--------------------------|--------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------|--------------------------------------------------|------------------------------|----------------------------|------------|
| 1 | Windows | Windows - Admin night logon | Alert on Windows login events when detected outside business hours | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 2 | Windows | Windows - Admin task as user | Alert when admin task is initiated by regular user. Windows event id 4732 is verified towards static admin list. If the user does not belong to admin list AND the event is seen than we generate alert. Static Admin list is a logstash disctionary file that needs to be created manually. During Logstash lookup a field user.role:admin is added to an event.4732: A member was added to a security-enabled local group | winlogbeat-* | winlogbeatLogstash admin dicstionary lookup file | Widnows Security Eventlog | Every 1min | 1 |
| 3 | Windows | Windows - diff IPs logon | Alert when Windows logon process is detected and two or more different IP addressed are seen in source field. Timeframe is last 15min.Detection is based onevents 4624 or 1200.4624: An account was successfully logged on1200: Application token success | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min, for last 15min | 1 |
| 4 | Windows | Windows - Event service error | Alert when Windows event 1108 is matched1108: The event logging service encountered an error | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 5 | Windows | Windows - file insufficient privileges | Alert when Windows event 5145 is matched5145: A network share object was checked to see whether client can be granted desired accessEvery time a network share object (file or folder) is accessed, event 5145 is logged. If the access is denied at the file share level, it is audited as a failure event. Otherwise, it considered a success. This event is not generated for NTFS access. | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min, for last 15min | 50 |
| 6 | Windows | Windows - Kerberos pre-authentication failed | Alert when Windows event 4625 or 4771 is matched 4625: An account failed to log on 4771: Kerberos pre-authentication failed | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 7 | Windows | Windows - Logs deleted | Alert when Windows event 1102 OR 104 is matched1102: The audit log was cleared104: Event log cleared | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 8 | Windows | Windows - Member added to a security-enabled global group | Alert when Windows event 4728 is matched4728: A member was added to a security-enabled global group | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 9 | Windows | Windows - Member added to a security-enabled local group | Alert when Windows event 4732 is matched4732: A member was added to a security-enabled local group | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 10 | Windows | Windows - Member added to a security-enabled universal group | Alert when Windows event 4756 is matched4756: A member was added to a security-enabled universal group | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 11 | Windows | Windows - New device | Alert when Windows event 6414 is matched6416: A new external device was recognized by the system | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 12 | Windows | Windows - Package installation | Alert when Windows event 4697 is matched 4697: A service was installed in the system | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 13 | Windows | Windows - Password policy change | Alert when Windows event 4739 is matched4739: Domain Policy was changed | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 14 | Windows | Windows - Security log full | Alert when Windows event 1104 is matched1104: The security Log is now full | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 15 | Windows | Windows - Start up | Alert when Windows event 4608 is matched 4608: Windows is starting up | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 16 | Windows | Windows - Account lock | Alert when Windows event 4740 is matched4740: A User account was Locked out | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 17 | Windows | Windows - Security local group was changed | Alert when Windows event 4735 is matched4735: A security-enabled local group was changed | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 18 | Windows | Windows - Reset password attempt | Alert when Windows event 4724 is matched4724: An attempt was made to reset an accounts password | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 19 | Windows | Windows - Code integrity changed | Alert when Windows event 5038 is matched5038: Detected an invalid image hash of a fileInformation: Code Integrity is a feature that improves the security of the operating system by validating the integrity of a driver or system file each time it is loaded into memory. Code Integrity detects whether an unsigned driver or system file is being loaded into the kernel, or whether a system file has been modified by malicious software that is being run by a user account with administrative permissions. On x64-based versions of the operating system, kernel-mode drivers must be digitally signed.The event logs the following information: | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 20 | Windows | Windows - Application error | Alert when Windows event 1000 is matched1000: Application error | winlogbeat-* | winlogbeat | Widnows Application Eventlog | Every 1min | 1 |
| 21 | Windows | Windows - Application hang | Alert when Windows event 1001 OR 1002 is matched1001: Application fault bucket1002: Application hang | winlogbeat-* | winlogbeat | Widnows Application Eventlog | Every 1min | 1 |
| 22 | Windows | Windows - Audit policy changed | Alert when Windows event 4719 is matched4719: System audit policy was changed | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 23 | Windows | Windows - Eventlog service stopped | Alert when Windows event 6005 is matched6005: Eventlog service stopped | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 24 | Windows | Windows - New service installed | Alert when Windows event 7045 OR 4697 is matched7045,4697: A service was installed in the system | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 25 | Windows | Windows - Driver loaded | Alert when Windows event 6 is matched6: Driver loadedThe driver loaded events provides information about a driver being loaded on the system. The configured hashes are provided as well as signature information. The signature is created asynchronously for performance reasons and indicates if the file was removed after loading. | winlogbeat-* | winlogbeat | Widnows System Eventlog | Every 1min | 1 |
| 26 | Windows | Windows - Firewall rule modified | Alert when Windows event 2005 is matched2005: A Rule has been modified in the Windows firewall Exception List | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 27 | Windows | Windows - Firewall rule add | Alert when Windows event 2004 is matched2004: A firewall rule has been added | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
| 28 | | Windows - Firewall rule deleted | Alert when Windows event 2006 or 2033 or 2009 is matched2006,2033,2009: Firewall rule deleted | winlogbeat-* | winlogbeat | Widnows Security Eventlog | Every 1min | 1 |
Playbooks¶
Energy Logserver has a set of predefined set of rules and activities (called Playbook) that can be attached to a registered event in the Alert module. Playbooks can be enriched with scripts that can be launched together with Playbook.
Create Playbook¶
To add a new playbook, go to the Alert module, select the Playbook tab and then Create Playbook
In the Name field, enter the name of the new Playbook.
In the Text field, enter the content of the Playbook message.
In the Script field, enter the commands to be executed in the script.
To save the entered content, confirm with the Submit button.
Playbooks list¶
To view saved Playbook, go to the Alert module, select the Playbook tab and then Playbooks list:
To view the content of a given Playbook, select the Show button.
To enter the changes in a given Playbook or in its script, select the Update button. After making changes, select the Submit button.
To delete the selected Playbook, select the Delete button.
Linking Playbooks with alert rule¶
You can add a Playbook to the Alert while creating a new Alert or by editing a previously created Alert.
To add Palybook to the new Alert rule, go to the Create alert rule tab and in the Playbooks section use the arrow keys to move the correct Playbook to the right window.
To add a Palybook to existing Alert rule, go to the Alert rule list tab with the correct rule select the Update button and in the Playbooks section use the arrow keys to move the correct Playbook to the right window.
Playbook verification¶
When creating an alert or while editing an existing alert, it is possible that the system will indicate the most-suited playbook for the alert. For this purpose, the Validate button is used, which starts the process of searching the existing playbook and selects the most appropriate ones.
Risks¶
Energy Logserver allows you to estimate the risk based on the collected data. The risk is estimated based on the defined category to which the values from 0 to 100 are assigned.
Information on the defined risk for a given field is passed with an alert and multiplied by the value of the Rule Importance parameter.
Create category¶
To add a new risk Category, go to the Alert module, select the Risks tab and then Create Cagtegory.
Enter the Name for the new category and the category Value.
Category list¶
To view saved Category, go to the Alert module, select the Risks tab and then Categories list:
To view the content of a given Category, select the Show button.
To change the value assigned to a category, select the Update button. After making changes, select the Submit button.
To delete the selected Category, select the Delete button.
Create risk¶
To add a new playbook, go to the Alert module, select the Playbook tab and then Create Playbook
In the Index pattern field, enter the name of the index pattern. Select the Read fields button to get a list of fields from the index. From the box below, select the field name for which the risk will be determined.
From the Timerange field, select the time range from which the data will be analyzed.
Press the Read valules button to get values from the previously selected field for analysis.
Next, you must assign a risk category to the displayed values. You can do this for each value individually or use the check-box on the left to mark several values and set the category globally using the Set global category button. To quickly find the right value, you can use the search field.
After completing, save the changes with the Submit button.
List risk¶
To view saved risks, go to the Alert module, select the Risks tab and then Risks list:
To view the content of a given Risk, select the Show button.
To enter the changes in a given Risk, select the Update button. After making changes, select the Submit button.
To delete the selected Risk, select the Delete button.
Linking risk with alert rule¶
You can add a Risk key to the Alert while creating a new Alert or by editing a previously created Alert.
To add Risk key to the new Alert rule, go to the Create alert rule tab and after entering the index name, select the Read fields button and in the Risk key field, select the appropriate field name. In addition, you can enter the validity of the rule in the Rule Importance field (in the range 1-100%), by which the risk will be multiplied.
To add Risk key to the existing Alert rule, go to the Alert rule list, tab with the correct rule select the Update button. Use the Read fields button and in the Risk key field, select the appropriate field name. In addition, you can enter the validity of the rule in the Rule Importance.
Risk calculation algorithms¶
The risk calculation mechanism performs the aggregation of the risk field values. We have the following algorithms for calculating the alert risk (Aggregation type):
- min - returns the minimum value of the risk values from selected fields;
- max - returns the maximum value of the risk values from selected fields;
- avg - returns the average of risk values from selected fields;
- sum - returns the sum of risk values from selected fields;
- custom - returns the risk value based on your own algorithm
Adding a new risk calculation algorithm¶
The new algorithm should be added in the ./elastalert_modules/playbook_util.py file in the calculate_risk method. There is a sequence of conditional statements for already defined algorithms:
#aggregate values by risk_key_aggregation for rule
if risk_key_aggregation == "MIN":
value_agg = min(values)
elif risk_key_aggregation == "MAX":
value_agg = max(values)
elif risk_key_aggregation == "SUM":
value_agg = sum(values)
elif risk_key_aggregation == "AVG":
value_agg = sum(values)/len(values)
else:
value_agg = max(values)
To add a new algorithm, add a new sequence as shown in the above code:
elif risk_key_aggregation == "AVG":
value_agg = sum(values)/len(values)
elif risk_key_aggregation == "AAA":
value_agg = BBB
else:
value_agg = max(values)
where AAA is the algorithm code, BBB is a risk calculation function.
Using the new algorithm¶
After adding a new algorithm, it is available in the GUI in the Alert tab.
To use it, add a new rule according to the following steps:
- Select the
customvalue in theAggregationtype field; - Enter the appropriate value in the
Anyfield, e.g.risk_key_aggregation: AAA
The following figure shows the places where you can call your own algorithm:
Additional modification of the algorithm (weight)¶
Below is the code in the calcuate_risk method where category values are retrieved - here you can add your weight:
#start loop by tablicy risk_key
for k in range(len(risk_keys)):
risk_key = risk_keys[k]
logging.info(' >>>>>>>>>>>>>> risk_key: ')
logging.info(risk_key)
key_value = lookup_es_key(match, risk_key)
logging.info(' >>>>>>>>>>>>>> key_value: ')
logging.info(key_value)
value = float(self.get_risk_category_value(risk_key, key_value))
values.append( value )
logging.info(' >>>>>>>>>>>>>> risk_key values: ')
logging.info(values)
#finish loop by tablicy risk_key
#aggregate values by risk_key_aggregation form rule
if risk_key_aggregation == "MIN":
value_agg = min(values)
elif risk_key_aggregation == "MAX":
value_agg = max(values)
elif risk_key_aggregation == "SUM":
value_agg = sum(values)
elif risk_key_aggregation == "AVG":
value_agg = sum(values)/len(values)
else:
value_agg = max(values)
Risk_key is the array of selected risk key fields in the GUI.
A loop is made on this array and a value is collected for the categories in the line:
value = float(self.get_risk_category_value(risk_key, key_value))
Based on, for example, Risk_key, you can multiply the value of the value field by the appropriate weight. The value field value is then added to the table on which the risk calculation algorithms are executed.