Techniques
Sample rules
PingID New MFA Method After Credential Reset
- source: splunk
- technicques:
- T1621
- T1556.006
- T1098.005
Description
A common social engineering technique used by threat actors is the impersonation of a valid user to organizational support staff for a password reset. During the same support call or quickly afterwards the threat actor will request provisioning of a new MFA device. This does not require malware or phishing infrastructure and has proven to be successful in numerous historical attacks. This detection looks for the pattern of password reset, followed by MFA device provisioning.
Detection logic
`pingid` "result.message" = "*Device Paired*"
| rex field=result.message "Device (Unp)?(P)?aired (?<device_extract>.+)"
| eval src = coalesce('resources{}.ipaddress','resources{}.devicemodel'), user = upper('actors{}.name'), reason = 'result.message'
| eval object=CASE(ISNOTNULL('resources{}.devicemodel'),'resources{}.devicemodel',true(),device_extract)
| eval action=CASE(match('result.message',"Device Paired*"),"created",match('result.message', "Device Unpaired*"),"deleted")
| stats count min(_time) as firstTime, max(_time) as lastTime, values(reason) as reason by src,user,action,object
| join type=outer user [
| search `wineventlog_security` EventID IN(4723,4724)
| eval PW_Change_Time = _time, user = upper(user)
| fields user,src_user,EventID,PW_Change_Time]
| eval timeDiffRaw = round(lastTime - PW_Change_Time)
| eval timeDiff = replace(tostring(abs(timeDiffRaw) ,"duration"),"(\d*)\+*(\d+):(\d+):(\d+)","\2 hours \3 minutes")
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `security_content_ctime(PW_Change_Time)`
| where timeDiffRaw > 0 AND timeDiffRaw < 3600
| `pingid_new_mfa_method_after_credential_reset_filter`