tbs.sys - Clean (10/100) - DriverShield Analysis

Analysis of tbs.sys: clean verdict, risk score 10/100. 0 YARA matches. SHA256 8e6d3358d074c3f2. Kernel imports, IOCTL codes, MITRE ATT&CK, and code-signing details.

tbs.sys - Analysis Report

DriverShield analyzed the Windows kernel driver tbs.sys and assigned a verdict of Clean with a composite risk score of 10/100, indicating no notable risk signals (0-29 band).

Verdict	Clean (10/100)
YARA matches	0
File size	32736 bytes
Code-signing signer	Microsoft Windows
Analyzed	2026-03-22
SHA256	8e6d3358d074c3f2fc95bf6c4ae7af7929b68de2e3cf68b279722dc1f7a07531
SHA1	4b273d13c6f07aa1c49580e94e66f48b6dbc5749
MD5	32c91a398b84efd394cafab4cd436c43

Driver identity

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

File description	Export driver for kernel mode TPM API
Product	Microsoft® Windows® Operating System
Company	Microsoft Corporation
Original filename	TBS.SYS
Internal name	TBS.SYS
File version	10.0.19041.4355 (WinBuild.160101.0800)
Copyright	© Microsoft Corporation. All rights reserved.

How the 10/100 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	18 / 100
IOCTL dispatch surface	24 / 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 (6)

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

API	Risk	Why it matters
ZwOpenKey	low	Standard kernel API - generally benign
ZwClose	low	Standard kernel API - generally benign
RtlInitUnicodeString	low	Standard kernel API - generally benign
ZwQueryValueKey	low	Standard kernel API - generally benign
ZwCreateFile	low	Standard kernel API - generally benign
ExAllocatePool2	low	Standard kernel API - generally benign

IOCTL dispatch codes (8)

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
0x0022C19C	medium	METHOD_BUFFERED	FILE_DEVICE_UNKNOWN Function #103
0x0022C01C	medium	METHOD_BUFFERED	FILE_DEVICE_UNKNOWN Function #7
0x00343DC8	medium	METHOD_BUFFERED	FILE_DEVICE_DISK Function #3954
0x0022C194	medium	METHOD_BUFFERED	FILE_DEVICE_UNKNOWN Function #101
0x00802484	medium	METHOD_BUFFERED	FILE_DEVICE_CUSTOM Function #2337
0x0080F002	medium	METHOD_OUT_DIRECT	FILE_DEVICE_CUSTOM Function #3072
0x003403A4	medium	METHOD_BUFFERED	FILE_DEVICE_DISK Function #233
0x0034002E	medium	METHOD_OUT_DIRECT	FILE_DEVICE_DISK Function #11

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	0x2911	0x2A00	6.19	CODE, EXEC, READ
.rdata	0x0E98	0x1000	4.27	IDATA, READ
.data	0x00F8	0x0200	0.36	IDATA, READ, WRITE
.pdata	0x0354	0x0400	3.6	IDATA, READ
.idata	0x02DC	0x0400	3.21	IDATA, READ
PAGE	0x0168	0x0200	4.47	CODE, EXEC, READ
.edata	0x0208	0x0400	3.13	IDATA, READ
INIT	0x007C	0x0200	1.69	CODE, EXEC, READ, DISCARD
GFIDS	0x0060	0x0200	0.87	IDATA, READ, DISCARD
.rsrc	0x0408	0x0600	2.5	IDATA, READ, DISCARD
.reloc	0x0160	0x0200	2.95	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 (5)

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
T1543.003	Windows Service	Persistence
T1547.001	Registry Run Keys	Persistence
T1652	Device Driver Discovery	Discovery

Code-signing chain

Signer	Microsoft Windows
Signer organisation	Microsoft Corporation
Issuer	Microsoft Windows Production PCA 2011
Serial	3300000460CF42A912315F6FB3000000000460
Valid from	2023-11-16 19:20 UTC
Valid until	2024-11-14 19:20 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 tbs.sys

Is tbs.sys safe?

Based on DriverShield static and dynamic analysis, tbs.sys is assessed as clean, with no notable risk signals. Its composite risk score is 10/100 (verdict: clean). Always validate findings independently before acting.

What is the risk score of tbs.sys?

tbs.sys has a DriverShield composite risk score of 10/100, placing it in the clean verdict band. SHA256: 8e6d3358d074c3f2fc95bf6c4ae7af7929b68de2e3cf68b279722dc1f7a07531.

What is tbs.sys?

tbs.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