Kerberoasting Activity - Initial Query

Status: test
Severity: medium
Log source: product windows, service security
Author: @kostastsale
Source: github.com/SigmaHQ/sigma

This rule will collect the data needed to start looking into possible kerberoasting activity. Further analysis or computation within the query is needed focusing on requests from one specific host/IP towards multiple service names within a time period of 5 seconds. You can then set a threshold for the number of requests and time between the requests to turn this into an alert.

MITRE ATT&CK coverage

Tactic	Techniques
Credential Access	`T1558.003` Steal or Forge Kerberos Tickets: Kerberoasting

Event coverage

Provider	Event	Title
Security-Auditing	Event ID 4769	A Kerberos service ticket was requested.

Rule body yaml

title: Kerberoasting Activity - Initial Query
id: d04ae2b8-ad54-4de0-bd87-4bc1da66aa59
status: test
description: |
    This rule will collect the data needed to start looking into possible kerberoasting activity.
    Further analysis or computation within the query is needed focusing on requests from one specific host/IP towards multiple service names within a time period of 5 seconds.
    You can then set a threshold for the number of requests and time between the requests to turn this into an alert.
references:
    - https://www.trustedsec.com/blog/art_of_kerberoast/
    - https://adsecurity.org/?p=3513
author: '@kostastsale'
date: 2022-01-21
modified: 2025-10-19
tags:
    - attack.credential-access
    - attack.t1558.003
logsource:
    product: windows
    service: security
detection:
    selection:
        EventID: 4769
        Status: '0x0' # Translated as status from failure code field. Query only for successes
        TicketEncryptionType: '0x17' # RC4 ticket encryption type
    filter_main_krbtgt:
        ServiceName|endswith:
            - 'krbtgt' # Ignore requests for the krbtgt service
            - '$' # Ignore requests from service names that end with $ which are associated with genuine kerberos traffic
    filter_main_machine_accounts:
        TargetUserName|contains: '$@' # Ignore requests from machines
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Legacy applications.
level: medium

Stages and Predicates

Stage 0: `condition`

selection and not 1 of filter_main_*

Stage 1: `selection`

selection:
    EventID: 4769
    Status: '0x0'
    TicketEncryptionType: '0x17'

Stage 2: `not filter_main_*`

filter_main_krbtgt:
    ServiceName|endswith:
        - 'krbtgt'
        - '$'
filter_main_machine_accounts:
    TargetUserName|contains: '$@'

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

Field	Kind	Excluded values
`ServiceName`	ends_with	`$`
`ServiceName`	ends_with	`krbtgt`
`TargetUserName`	match	`$@`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`Status`	eq	`0x0` corpus 3 (kusto 2, sigma 1)
`TicketEncryptionType`	eq	`0x17` corpus 8 (splunk 4, sigma 3, kusto 1)

`j` / `k`	Scroll down / up
`d` / `u`	Half-page down / up
`gg` / `G`	Top / bottom
`h` / `l`	History back / forward
`f`	Follow link (`Shift` = new tab)
`/`	Focus search
`?`	Toggle this help
`↑` / `↓`	Navigate search results
`Enter`	Open highlighted result
`Esc`	Close results / dialog

`type:`	`events` / `rules` / `providers`
`vendor:`	`sigma` / `elastic` / `splunk` / `kusto` / `chronicle` (vendor name alone also works: `sigma:`, `kql:`, `secops:`…)
`tactic:`	TA-id, slug, or name: `credential_access`, `TA0006`
`technique:`	technique or sub-technique ID: `T1003`, `T1003.001` (alias `tech:`)
`severity:`	`critical` / `high` / `medium` / `low` / `informational` (alias `sev:`)
`risk_score`	Numeric comparison on the Elastic risk score (0 to 100): `risk_score>50`, `risk_score<=20`, `risk_score=99` (alias `risk`; Elastic rules only)
`stages:`	Rules with exactly N pipeline stages
`correlation:`	`single_event` / `sequence` / `alternatives` / `alternatives_cross_log` / `all_required` / `correlated`
`with:`	Co-occurrence event-id; stacks (`with:4624 with:4769`) to require all, while a comma list in one occurrence (`with:4624,4769`) is an either-or group. Implies multi-event
`like:`	Structural neighbors of a rule slug (equivalents + subsumption stricter / broader): `like:comsvcs_lsass_memory_dump-splunk-sysmon`
`groupby:`	Entity-grouping substring match against `group_by_keys`: `groupby:user`, `groupby:host`
`uses:`	Rules whose predicate tree touches the field (any kind, any value): `uses:CommandLine`
`excludes:`	Rules with top-level `not()` clauses on the field (FP whitelists): `excludes:ParentImage`
`field:` / `value:`	Predicate search; narrows rule cards to those with a matching leaf and drives the indicator tier. Unquoted = substring, wildcards allowed (`value:mimikatz`)
`indicator:`	Shorthand for `field:F value:V`: `indicator:Image=*\powershell.exe`
`kind:`	Filter by predicate kind. Narrows rule cards to those carrying a matching predicate leaf (`vendor:elastic kind:cidr_match`) and drives the indicator tier: `contains` / `starts_with` / `ends_with` / `regex` / `cidr` / `eq` / `in` … (operator aliases `op:`/`match:`)
`has:` / `no:`	`sample`, `field`, `notes`, `refs`, `trace`, `thirdparty`, `rule`, `pattern`, `timewindow`, `threshold`, `newterms`, `sigma`/`elastic`/`splunk`/`kusto`/`chronicle`
`-op:val`	Exclude matches; works on most operators but not `type:`/`like:`/`has:`/`no:` (use `no:<flag>` to exclude a rule flag): `tactic:execution -vendor:splunk`. Standalone `-kind:`/`-field:`/`-value:` drop every rule carrying a matching predicate leaf (`type:rules -kind:is_null`)
`field:"…"` / `value:"…"`	Quoted value = anchored exact match (also allows spaces): `value:"net user"`
`a,b`	Comma = OR inside one operator (`vendor:sigma,elastic`, `severity:high,critical`); repeating a facet merges the same way. `field:`/`value:` never split (literal commas)
`vendors:` / `stage:`	Singular and plural spellings fold to the canonical operator and value: `tactics:` = `tactic:`, `type:event` = `type:events`, `correlation:sequences` = `correlation:sequence`, `has:thresholds` = `has:threshold`
`"quoted phrase"`	Exact-match a multi-word phrase (free text)

Kerberoasting Activity - Initial Query

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: `condition`

Stage 1: `selection`

Stage 2: `not filter_main_*`

Exclusions

Indicators

Keyboard shortcuts

Search operators

Kerberoasting Activity - Initial Query

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: condition

Stage 1: selection

Stage 2: not filter_main_*

Exclusions

Indicators

Stage 0: `condition`

Stage 1: `selection`

Stage 2: `not filter_main_*`