Steal or Forge Kerberos Tickets: AS-REP Roasting T1558.004

Tactic: Credential Access

Adversaries may reveal credentials of accounts that have disabled Kerberos preauthentication by Password Cracking Kerberos messages.

Events covered

5 catalog events are tagged with this technique by at least one rule.

Authoring guide

Patterns shared across the 10 rules above: which fields they filter on, what specific values they look for, and what they exclude. The catalog normalizes field names across vendors so Sigma's Image, Elastic's process.name, and Splunk's process_name collapse into one row. Each rule contributes at most once per row.

Fields filtered most (19 distinct)

The fields most rules look at when detecting this technique. The How column shows the operators authors use (eq, wildcard, regex_match, match) and how often each appears. Sample values are concrete examples to start from, not an exhaustive list.

FieldRulesHowSample values
EventID4eq 44104, 4738
ScriptBlockText3contains 34194304, doesnotrequirepreauth:$true, get-aduser, get-domainuser, preauthnotrequired
CommandLine2contains 2, eq 1, in 1 -p , -u , asreproast, harvest, kerberoast
PreAuthType2eq 20
src_ip2eq 1, ne 1%domain_controllers_ips%, 127.0.0.1
Channel1eq 1, in 1
DestinationPort1eq 188
Image1is_not_null 1
NewUACList1eq 1USER_DONT_REQUIRE_PREAUTH
OriginalFileName1eq 1nxc.exe
ServiceName1eq 1krbtgt
ServiceSid1ends_with 1-502
Status1eq 10
TicketEncryptionType1eq 10x17
UserAccountControl1contains 1%%2096

Top indicator values (50 distinct)

Specific (field, operator, value) combinations the rules check for, ranked by how many rules under this technique use each one. The Corpus reach column counts how many rules across the entire catalog (any technique) check the same combination. High numbers point to widely-used indicators that are likely noisy on their own; combine them with another condition for useful signal. Blank means the combination is specific to rules under this technique. Click a value to expand the rules under this technique that use it.

FieldKindValueRules (here)Corpus reach
EventIDeq
4104
3268
PreAuthTypeeq
0
22
CommandLinecontains
-p
110
CommandLinecontains
-u
18
CommandLinecontains
asreproast
1
CommandLinecontains
harvest
1
CommandLinecontains
kerberoast
1
CommandLinecontains
monitor /interval
1
CommandLinecontains
ptt /ticket
1
CommandLineeq
* asktgs* /service:*
1
CommandLineeq
* asktgt* /user:*
1
CommandLineeq
* brute* /password:*
1
CommandLineeq
* brute* /passwords:*
1
CommandLineeq
* golden* /user:*
1
CommandLineeq
* renew* /ticket:*
1
CommandLineeq
* silver* /service:*
1
CommandLinein
* --*
1
CommandLinein
* -M *
1
CommandLinein
* -x *
1
CommandLinein
* ftp *
1
CommandLinein
* ldap *
1
CommandLinein
* mssql *
1
CommandLinein
* nfs *
1
CommandLinein
* rdp *
1
CommandLinein
* smb *
1
CommandLinein
* ssh *
1
CommandLinein
* vnc *
1
CommandLinein
* winrm *
1
CommandLinein
* wmi *
1
DestinationPorteq
88
15

Exclusions (11 distinct)

Field/operator/value combinations excluded by rules under this technique (top-level not() clauses), sorted by how many rules exclude each. These are the false-positive paths the community has learned to filter out. A new rule that ignores the high-count entries here will likely fire on the same noisy paths. Click a value to expand the rules under this technique that exclude it.

FieldKindValueRules excluding
Imagewildcard
?:\windows\system32\lsass.exe
1
Imagewildcard
\device\harddiskvolume*\windows\system32\lsass.exe
1
Imagewildcard
\device\harddiskvolume*\windows\system32\svchost.exe
1
Imagewildcard
c:\program files\omnissa\horizon\server\bin\ws_tomcatservice.exe
1
Imagewildcard
c:\program files\vmware\vmware view\server\bin\ws_tomcatservice.exe
1
Imagewildcard
c:\windows\system32\svchost.exe
1
Imagewildcard
f:\igel\remotemanager\*\bin\tomcat10.exe
1
Processes.oseq
Linux
1
src_ipeq
%domain_controllers_ips%
1
user.idin
S-1-5-18
1
user.idin
S-1-5-20
1

Rules under this technique

Every rule in the catalog tagged with this technique, grouped by vendor. Click a rule title for its full predicates, exclusions, and indicators.

Platform (all)
Domain (all)

Sigma 2 rules

Elastic 2 rules

Splunk 6 rules