Decoders Syntax

Options

decoder

The attributes list below defines a decoder.

Attribute

Description

id

The ID of the decoder

name

The name of the decoder

type

The type of the decoder

status

The status of the decoder

parent

It is used to link a subordinate codeblock to his parent.

Default Value

n/a

Allowed values

Any decoder name

accumulate

Allow Wazuh to track events over multiple log messages based on a decoded id.

Note

Requires a regex populating the id field.

Example of use

<accumulate />

program_name

It defines the name of the program with which the decoder is associated.

Default Value

n/a

Allowed values

Any sregex expression

prematch

It attempts to find a match within the log for the string defined.

Default Value

n/a

Allowed values

Any sregex expression

The attribute below is optional, it allows to discard some of the content of the entry.

Attribute

Value

offset

after_regex

regex

Default Value

n/a

Allowed values

Any regex expression

The attribute below is optional, it allows to discard some of the content of the entry.

Attribute

Value

offset

after_regex

after_parent

after_prematch

order

It defines what the parenthesis groups contain and the order in which they were received.

Default Value

n/a

Static fields

srcuser

Extracts the source username

dstuser

Extracts the destination (target) username

user

An alias to dstuser (only one of the two can be used)

srcip

Source ip

dstip

Destination ip

srcport

Source port

dstport

Destination port

protocol

Protocol

id

Event id

url

Url of the event

action

Event action (deny, drop, accept, etc)

status

Event status (success, failure, etc)

extra_data

Any extra data

Dynamic fields

Any string not included in the previous list

fts

It is used to designate a decoder as one in which the first time it matches the administrator would like to be alerted.

Default Value

n/a

Allowed values

location

Where the log came from

srcuser

Extracts the source username

dstuser

Extracts the destination (target) username

user

An alias to dstuser (only one of the two can be used)

srcip

Source ip

dstip

Destination ip

srcport

Source port

dstport

Destination port

protocol

Protocol

id

Event id

url

Url of the event

action

Event action (deny, drop, accept, etc)

status

Event status (success, failure, etc)

extra_data

Any extra data

ftscomment

It adds a comment to a decoder when <fts> tag is used.

Default Value

n/a

Allowed values

Any string

plugin_decoder

Use a specific plugin decoder to decode the incoming fields. It is useful for particular cases where it would be tricky to extract the fields by using regexes.

Default Value

n/a

Allowed values

PF_Decoder

SymantecWS_Decoder

SonicWall_Decoder

OSSECAlert_Decoder

JSON_Decoder

The attribute below is optional, it allows to start the decode process after a particular point of the log.

Attribute

Value

offset

after_parent

after_prematch

An example of its use is described at the JSON decoder section.

use_own_name

Allows to set the name of the child decoder from the name attribute instead of using the name of the parent decoder.

Default Value

n/a

Allowed values

true

json_null_field

Specify how to treat the NULL fields coming from the JSON events. Only for the JSON decoder.

Default Value

string

Allowed values

string (It shows the NULL value as string)

discard (It discard NULL fields and doesn't store them into the alert)

empty (It shows the NULL field as an empty field)