Detect Firmware Corruption in Elastic Security
Adversaries may overwrite or corrupt the flash memory contents of system BIOS or other firmware in devices attached to a system in order to render them inoperable or unable to boot, thus denying the availability to use the devices and/or the system. Firmware is software that is loaded and executed from non-volatile memory on hardware devices in order to initialize and manage device functionality. These devices may include the motherboard, hard drive, or video cards. Real-world examples include TrickBot's 'Trickboot' module (2020), which can write or erase UEFI/BIOS firmware of a compromised device, and Bad Rabbit ransomware, which installed a modified bootloader to prevent normal boot-up. Firmware corruption often results in permanent hardware denial-of-availability and may be combined with data destruction for maximum impact.
MITRE ATT&CK
- Tactic
- Impact
- Technique
- T1495 Firmware Corruption
- Canonical reference
- https://attack.mitre.org/techniques/T1495/
Elastic Detection Query
sequence by host.id with maxspan=5m
[process where event.type == "start" and (
process.name : ("rw.exe", "rw64.exe", "rweverything.exe", "chipsec.exe", "chipsec_main.exe", "flashrom.exe", "fpt.exe", "fptw.exe", "fptw64.exe", "afuwin.exe", "afuwin64.exe", "afudos.exe", "meinfo.exe", "meinfowin.exe", "meinfowin64.exe", "amidewin.exe", "amidewin64.exe", "h2offt.exe", "h2offt-w.exe", "winphlash.exe", "winphlash64.exe", "ubuild.exe", "ubu.exe") or
process.args : ("--write", "--erase", "--flash", "spi write", "spi.write", "spi_write", "bios write", "uefi write", "flash write", "nvram write", "WRITESPI", "/WRITESPI", "chipsec_util spi write", "flashrom -w", "flashrom --write") or
(process.name : ("powershell.exe", "pwsh.exe") and process.args : ("Set-SecureBootUEFI", "Set-UEFIVariable", "bcdedit") and process.args : ("/set", "/delete", "/deletevalue"))
)]
[any where event.category == "driver" and
file.name : ("rw.sys", "rwdrv.sys", "winio.sys", "winio32.sys", "winio64.sys", "physmem.sys", "pmem.sys", "dbutil_2_3.sys", "rtcore64.sys")
]Detects firmware corruption attempts (T1495) by correlating known firmware manipulation tool execution with suspicious kernel driver loads. Covers RWEverything, Chipsec, flashrom, AFU tools, and UEFI/BCD tampering via PowerShell. Sequences process start events with driver load events on the same host within 5 minutes for high-confidence alerting.
Data Sources
Required Tables
False Positives & Tuning
- Legitimate BIOS update utilities run by IT/hardware teams during scheduled maintenance windows (e.g., vendor-supplied HP, Dell, Lenovo BIOS updaters that bundle fpt.exe or h2offt.exe)
- Security researchers or red team operators running Chipsec or RWEverything on dedicated test systems for firmware auditing or vulnerability research
- System administrators using bcdedit to configure boot options for dual-boot environments or to enable/disable Secure Boot features during OS deployment
Other platforms for T1495
Testing Methodology
Validate this detection against 5 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.
- Test 1CHIPSEC UEFI Variable Enumeration — Read-Only Firmware Reconnaissance
Expected signal: Sysmon Event ID 1: Process Create with Image=python.exe, CommandLine containing 'chipsec_util.py uefi var-list'. Sysmon Event ID 6: Driver load for chipsec.sys (or chipsec_hlpr.sys) from a temp or install directory. Security Event ID 7045: New service installed for the CHIPSEC kernel driver. Windows may prompt for UAC on driver installation.
- Test 2RW-Everything Hardware Access Tool Execution with Ring-0 Driver Load
Expected signal: Sysmon Event ID 1: Process Create with Image=Rw.exe and CommandLine containing '/Command="PCI 0 0 0 0 10"'. Sysmon Event ID 6: Driver load for rw.sys from tool directory or System32\drivers\. Security Event ID 7045: New service named 'RW' registered pointing to rw.sys. Service exits after tool completes but driver load telemetry persists.
- Test 3PowerShell BCD Store Modification — Bad Rabbit Bootloader Tamper Simulation
Expected signal: Sysmon Event ID 1: Process Create for powershell.exe with CommandLine containing 'bcdedit /set' and ExecutionPolicy Bypass. Two additional Sysmon EventCode=1 events for bcdedit.exe child processes. Security Event ID 4688 (if command-line auditing enabled) for both bcdedit invocations. PowerShell ScriptBlock Log Event ID 4104 capturing the full command.
- Test 4Linux flashrom SPI Flash Probe — Non-Destructive Hardware Reconnaissance
Expected signal: Linux auditd EXECVE record with a=flashrom, argv containing '-p', 'internal', '--no-action', '-V'. Syslog entry capturing sudo invocation and flashrom execution. On systems with Sysmon for Linux (EventID 1): Process Create event for flashrom. /var/log/auth.log entry recording sudo authentication for the flashrom command.
- Test 5Intel Flash Programming Tool (FPT) Flash Descriptor Read
Expected signal: Sysmon Event ID 1: Process Create with Image=fptw64.exe, CommandLine containing '-DESC -d'. Sysmon Event ID 11: File Create event for df00tech_flashdesc.bin in %TEMP%. Security Event ID 7045 may appear if FPT installs a kernel service for hardware access. The .bin file size will reflect the flash descriptor region size (typically 4KB).
References (8)
- https://attack.mitre.org/techniques/T1495/
- https://securelist.com/bad-rabbit-ransomware/82851/
- https://eclypsium.com/research/trickbot-now-offers-trickboot-persist-brick-profit/
- https://www.cisa.gov/uscert/ncas/alerts/aa22-057a
- https://cyber.dhs.gov/assets/report/ar-16-20173.pdf
- https://chipsec.github.io/
- https://www.flashrom.org/
- https://web.archive.org/web/20190508170055/https://www.symantec.com/security-center/writeup/2000-122010-2655-99
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