nvflsh64.sys - Suspicious (58/100) - DriverShield Analysis

Analysis of nvflsh64.sys: suspicious verdict, risk score 58/100. 0 YARA matches, 0/76 multi-engine detections. SHA256 a899b659b08fbae3. Kernel imports, IOCTL codes, MITRE ATT&CK, and code-signing details.

nvflsh64.sys - Analysis Report

DriverShield analyzed the Windows kernel driver nvflsh64.sys and assigned a verdict of Suspicious with a composite risk score of 58/100, indicating some risk signals warranting review (30-59 band).

Verdict	Suspicious (58/100)
YARA matches	0
Multi-engine detections	0 / 76
File size	15648 bytes
Code-signing signer	Symantec Time Stamping Services CA - G2
Analyzed	2026-09-06
SHA256	a899b659b08fbae30b182443be8ffb6a6471c1d0497b52293061754886a937a3
SHA1	7667b72471689151e176baeba4e1cd9cd006a09a
MD5	d3e40644a91327da2b1a7241606fe559

How the 58/100 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	93 / 100
IOCTL dispatch surface	3 / 100
Known-vulnerable corpus	100 / 100
Code-signing state	80 / 100
Packing and entropy	0 / 100
Dynamic behaviour	0 / 100
CVE cross-reference	0 / 100

Kernel imports (11)

Kernel-mode APIs resolved from the Import Address Table of nvflsh64.sys, ranked by exploitation relevance.

API	Risk	Why it matters
ZwMapViewOfSection	critical	Highly dangerous - potential for arbitrary code execution, memory corruption, or process termination
ObReferenceObjectByHandle	medium	Moderate risk - system modification capability
KeBugCheckEx	medium	Moderate risk - system modification capability
RtlInitUnicodeString	low	Standard kernel API - generally benign
ExAllocatePoolWithTag	low	Standard kernel API - generally benign
IoCreateDevice	low	Standard kernel API - generally benign
IoDeleteSymbolicLink	low	Standard kernel API - generally benign
ZwClose	low	Standard kernel API - generally benign
IoCreateSymbolicLink	low	Standard kernel API - generally benign
IoDeleteDevice	low	Standard kernel API - generally benign
IofCompleteRequest	low	Standard kernel API - generally benign

IOCTL dispatch codes (1)

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
0x002200F0	medium	METHOD_BUFFERED	FILE_DEVICE_UNKNOWN Function #60

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	0x0930	0x0A00	5.46	CODE, EXEC, READ
.rdata	0x0208	0x0400	2.44	IDATA, READ
.data	0x0118	0x0200	0.3	IDATA, READ, WRITE
.pdata	0x00D8	0x0200	1.76	IDATA, READ
INIT	0x02A2	0x0400	3.6	CODE, EXEC, READ, WRITE, DISCARD

Exploit mitigations

Control Flow Guard	Not enabled
ASLR	Not enabled
DEP	Not enabled
Integrity check	Not enforced
Mitigation score	5 / 100

No CFG - Control Flow Guard is not enabled. Indirect call targets are not validated, making the driver susceptible to control flow hijacking via corrupted function pointers or vtables.
No ASLR - ASLR is disabled. The driver loads at a predictable address, enabling reliable exploitation of memory corruption vulnerabilities.
No DEP - DEP is disabled. Data pages are executable, allowing shellcode execution from stack/heap buffers.
Expired Certificate - The driver is signed but the certificate has expired. Windows may still load it depending on revocation policy.

MITRE ATT&CK techniques (10)

Techniques this driver could enable if loaded by an adversary.

ID	Technique	Tactic
T1003.001	OS Credential Dumping: LSASS Memory	Credential Access
T1055.012	Process Hollowing	Defense Evasion
T1068	Exploitation for Privilege Escalation	Privilege Escalation
T1071	Application Layer Protocol	Command and Control
T1211	Exploitation for Defense Evasion	Defense Evasion
T1543.003	Windows Service	Persistence
T1553.002	Subvert Trust Controls: Code Signing	Defense Evasion
T1562.001	Impair Defenses	Defense Evasion
T1569.002	Service Execution	Execution
T1652	Device Driver Discovery	Discovery

Code-signing chain

Signer	Symantec Time Stamping Services CA - G2
Signer organisation	Symantec Corporation
Issuer	Thawte Timestamping CA
Serial	7E93EBFB7CC64E59EA4B9A77D406FC3B
Valid from	2012-12-21 00:00 UTC
Valid until	2020-12-30 23:59 UTC (expired)
Signature validity	Not verified

Certificate revision: 0x0200
Certificate type: PKCS#7
Chain: Symantec Time Stamping Services Signer - G4
Chain: VeriSign Class 3 Public Primary Certification Authority - G5
Chain: NVIDIA Corporation
Chain: VeriSign Class 3 Code Signing 2010 CA

Symbolic execution

Engine angr, status timeout, 53 paths explored at a maximum depth of 53. Vulnerability classes reached: 0. Exploitable paths: 0.

Corpus match: this hash is present in the known-vulnerable driver corpus DriverShield cross-references during analysis, which is why the score carries a full weighting on that component.

Frequently asked questions about nvflsh64.sys

Is nvflsh64.sys safe?

Based on DriverShield static and dynamic analysis, nvflsh64.sys shows some suspicious signals and warrants manual review. Its composite risk score is 58/100 (verdict: suspicious). Always validate findings independently before acting.

What is the risk score of nvflsh64.sys?

nvflsh64.sys has a DriverShield composite risk score of 58/100, placing it in the suspicious verdict band. SHA256: a899b659b08fbae30b182443be8ffb6a6471c1d0497b52293061754886a937a3.

What is nvflsh64.sys?

nvflsh64.sys is a Windows kernel-mode driver (.sys) analyzed by DriverShield for vulnerabilities, BYOVD abuse potential, and malware indicators. It is code-signed by Symantec Time Stamping Services CA - G2.