mssmbios.sys - Clean (25/100) - DriverShield Analysis

Analysis of mssmbios.sys: clean verdict, risk score 25/100. 0 YARA matches. SHA256 360a199a6d4690fe. Kernel imports, IOCTL codes, MITRE ATT&CK, and code-signing details.

mssmbios.sys - Analysis Report

DriverShield analyzed the Windows kernel driver mssmbios.sys and assigned a verdict of Clean with a composite risk score of 25/100, indicating no notable risk signals (0-29 band).

Verdict	Clean (25/100)
YARA matches	0
File size	47928 bytes
Code-signing signer	Microsoft Windows
Analyzed	2026-03-22
SHA256	360a199a6d4690fe248c6eaa4e84673f299fa4ca6c21e940f4df1b28216ba23c
SHA1	25138fceaa5b0e560618c4d8682d4e4fbc0f0d7d
MD5	db89919f84809686bd4f8c24eb6cb3fa

Driver identity

Version resource data embedded in the mssmbios.sys PE header, as extracted by the analysis engine.

File description	System Management BIOS Driver
Product	SystemManufacturer
Company	Microsoft Corporation
Original filename	smbios.sys
Internal name	smbios.sys
File version	10.0.19041.1 (WinBuild.160101.0800)
Copyright	© Microsoft Corporation. All rights reserved.

How the 25/100 score breaks down

Each component is scored 0-100 and then weighted into the composite. See the analysis methodology for the exact formula.

Component	Sub-score
Multi-engine consensus	0 / 100
YARA signature matches	0 / 100
Dangerous kernel imports	90 / 100
IOCTL dispatch surface	39 / 100
Known-vulnerable corpus	0 / 100
Code-signing state	80 / 100
Packing and entropy	0 / 100
Dynamic behaviour	0 / 100
CVE cross-reference	0 / 100

Kernel imports (12)

Kernel-mode APIs resolved from the Import Address Table of mssmbios.sys, ranked by exploitation relevance.

API	Risk	Why it matters
ZwSetValueKey	medium	Moderate risk - system modification capability
ZwDeleteKey	medium	Moderate risk - system modification capability
ZwCreateKey	medium	Moderate risk - system modification capability
ZwQuerySystemInformation	medium	Moderate risk - system modification capability
ZwOpenKey	low	Standard kernel API - generally benign
IoCreateDevice	low	Standard kernel API - generally benign
RtlInitAnsiString	low	Standard kernel API - generally benign
ZwClose	low	Standard kernel API - generally benign
RtlInitUnicodeString	low	Standard kernel API - generally benign
IoDeleteDevice	low	Standard kernel API - generally benign
IofCompleteRequest	low	Standard kernel API - generally benign
ExAllocatePoolWithTag	low	Standard kernel API - generally benign

IOCTL dispatch codes (13)

Control codes reachable through the driver dispatch routine. Codes tied to published exploit code are flagged, since they are the primary Bring Your Own Vulnerable Driver (BYOVD) entry points.

Code	Severity	Transfer	Description
0x0080BA1B	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #3718
0x9C403FFF	high	METHOD_NEITHER	CUSTOM_LENOVO Function #4095
0x002200F0	medium	METHOD_BUFFERED	FILE_DEVICE_UNKNOWN Function #60
0x00808F15	medium	METHOD_IN_DIRECT	FILE_DEVICE_CUSTOM Function #965
0x00809F15	medium	METHOD_IN_DIRECT	FILE_DEVICE_CUSTOM Function #1989
0x0034860D	medium	METHOD_IN_DIRECT	FILE_DEVICE_DISK Function #387
0x0034AB0D	medium	METHOD_IN_DIRECT	FILE_DEVICE_DISK Function #2755
0x00340030	medium	METHOD_BUFFERED	FILE_DEVICE_DISK Function #12
0x00808D89	medium	METHOD_IN_DIRECT	FILE_DEVICE_CUSTOM Function #866
0x0034B8CC	medium	METHOD_BUFFERED	FILE_DEVICE_DISK Function #3635
0x0080248C	medium	METHOD_BUFFERED	FILE_DEVICE_CUSTOM Function #2339
0x008024BC	medium	METHOD_BUFFERED	FILE_DEVICE_CUSTOM Function #2351
0x00340398	medium	METHOD_BUFFERED	FILE_DEVICE_DISK Function #230

PE sections

Section layout and Shannon entropy. High entropy in a code section is a packing or encryption indicator.

Section	Virtual size	Raw size	Entropy	Flags
.text	0x3958	0x3A00	6.15	CODE, EXEC, READ
.rdata	0x17C8	0x1800	4.61	IDATA, READ
.data	0x0678	0x0200	2.64	IDATA, READ, WRITE
.pdata	0x07B0	0x0800	4.35	IDATA, READ
.idata	0x0870	0x0A00	4	IDATA, READ
PAGE	0x19CB	0x1A00	5.98	CODE, EXEC, READ
INIT	0x021E	0x0400	3.81	CODE, EXEC, READ, DISCARD
GFIDS	0x0044	0x0200	0.64	IDATA, READ, DISCARD
.rsrc	0x08F0	0x0A00	4.95	IDATA, READ, DISCARD
.reloc	0x0430	0x0600	4.16	IDATA, READ, DISCARD

Exploit mitigations

Control Flow Guard	Enabled
ASLR	Enabled
DEP	Enabled
Integrity check	Not enforced
Mitigation score	85 / 100

CFG Enabled - Control Flow Guard is active - indirect calls are validated against a bitmap of valid targets at runtime.
ASLR Enabled - Address Space Layout Randomization is active - base address is randomized on each load.
DEP/NX Enabled - Data Execution Prevention is active - non-executable pages cannot be executed.
Expired Certificate - The driver is signed but the certificate has expired. Windows may still load it depending on revocation policy.

MITRE ATT&CK techniques (8)

Techniques this driver could enable if loaded by an adversary.

ID	Technique	Tactic
T1071	Application Layer Protocol	Command and Control
T1112	Modify Registry	Defense Evasion
T1211	Exploitation for Defense Evasion	Defense Evasion
T1543.003	Windows Service	Persistence
T1547.001	Registry Run Keys	Persistence
T1553.002	Subvert Trust Controls: Code Signing	Defense Evasion
T1569.002	System Services: Service Execution	Execution
T1652	Device Driver Discovery	Discovery

Code-signing chain

Signer	Microsoft Windows
Signer organisation	Microsoft Corporation
Issuer	Microsoft Windows Production PCA 2011
Serial	330000023241FB59996DCC4DFF000000000232
Valid from	2019-05-02 21:24 UTC
Valid until	2020-05-02 21:24 UTC (expired)
Signature validity	Not verified

Certificate revision: 0x0200
Certificate type: PKCS#7
Chain: Microsoft Windows Production PCA 2011

Symbolic execution

Engine angr, status no_findings, 0 paths explored at a maximum depth of 0. Vulnerability classes reached: 0. Exploitable paths: 0.

Frequently asked questions about mssmbios.sys

Is mssmbios.sys safe?

Based on DriverShield static and dynamic analysis, mssmbios.sys is assessed as clean, with no notable risk signals. Its composite risk score is 25/100 (verdict: clean). Always validate findings independently before acting.

What is the risk score of mssmbios.sys?

mssmbios.sys has a DriverShield composite risk score of 25/100, placing it in the clean verdict band. SHA256: 360a199a6d4690fe248c6eaa4e84673f299fa4ca6c21e940f4df1b28216ba23c.

What is mssmbios.sys?

mssmbios.sys is a Windows kernel-mode driver (.sys) analyzed by DriverShield for vulnerabilities, BYOVD abuse potential, and malware indicators. It is code-signed by Microsoft Windows.

Related: Other drivers signed by Microsoft Windows · What an IOCTL dispatch code is · BYOVD research index · full driver database · CVE library · code signing atlas