Techniques › T1542.001 › AN0275
AN0275 Analytic 0275
Windows · attack.mitre.org · ATT&CK Enterprise v19.2
<p>Unexpected write operations to BIOS/UEFI firmware regions or EFI boot partitions that do not correlate with legitimate vendor firmware updates. API calls or utilities such as fwupdate.exe or vendor flash tools executed from non-administrative or non-IT management accounts. Suspicious raw disk writes targeting System Firmware GUID partitions followed by abnormal reboot sequences.</p>
- Detects
- T1542.001 System Firmware
- Part of
- DET0099 Detection Strategy for T1542.001 Pre-OS Boot: System Firmware
Log sources and channels
Exactly as MITRE states them in x_mitre_log_source_references. Where a channel is vague, it is vague in the source; kevmap does not tidy it.
| Log source | Channel | Data component |
|---|---|---|
| WinEventLog:Security | EventCode=4688 | DC0032 Process Creation |
| WinEventLog:Sysmon | EventCode=9 | DC0054 Drive Access |
| WinEventLog:Sysmon | EventCode=11 | DC0039 File Creation |
Mutable elements
Parameters MITRE marks as environment-specific. These are the knobs you are expected to tune; they are why an analytic is not a rule.
| Field | Description |
|---|---|
AllowedFirmwareUpdateTools | Legitimate vendor tools permitted to perform firmware flashing or BIOS updates. |
TimeWindow | Expected time periods for approved firmware updates, used for correlating suspicious activity outside patch cycles. |
KnownGoodFirmwareHashes | Baseline hashes of vendor BIOS/UEFI firmware for integrity comparison. |