Valid Accounts: Default Accounts T1078.001
Tactics: Stealth, Persistence, Privilege Escalation, Initial Access
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Default accounts are those that are built-into an OS, such as the Guest or Administrator accounts on Windows systems. Default accounts also include default factory/provider set accounts on other types of systems, software, or devices, including the root user account in AWS, the root user account in ESXi, and the default service account in Kubernetes.
Events covered
4 catalog events are tagged with this technique by at least one rule.
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Security-Auditing | Event ID 4624 | An account was successfully logged on. |
| Security-Auditing | Event ID 4688 | A new process has been created. |
| ESF | exec | Process Execution (Notify) |
Authoring guide
Patterns shared across the 15 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 (30 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.
Top indicator values (41 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.
Exclusions (16 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.
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.
Sigma 4 rules
- Admin User Remote Logon
- Commvault QLogin with PublicSharingUser and GUID Password (CVE-2025-57788)
- Guest Account Enabled Via Sysadminctl
- Root Account Enable Via Dsenableroot
Elastic 2 rules
- Kubernetes Anonymous Request Authorized by Unusual User Agent
- Kubernetes Suspicious Assignment of Controller Service Account
Splunk 7 rules
- Account set to active via Net.exe (EDR)
- Account set to active via Net.exe (Sysmon)
- Account set to active via Net.exe (Windows Event Log)
- Okta New API Token Created
- Okta Phishing Detection with FastPass Origin Check
- Okta Suspicious Activity Reported
- Windows Guest Account Enabled Via Net.EXE