Analysis of WinFlash64.sys: vulnerable verdict, risk score 72/100. 2 YARA matches, 1/75 multi-engine detections. SHA256 316a27e2bdb86222. Kernel imports, IOCTL codes, MITRE ATT&CK, and code-signing details.
DriverShield analyzed the Windows kernel driver WinFlash64.sys and assigned a verdict of Vulnerable with a composite risk score of 72/100, indicating a known or likely vulnerability surface (60-79 band).
| Verdict | Vulnerable (72/100) |
| YARA matches | 2 |
| Multi-engine detections | 1 / 75 |
| File size | 13120 bytes |
| Code-signing signer | VeriSign Time Stamping Services CA |
| Analyzed | 2026-03-24 |
| SHA256 | 316a27e2bdb86222bc7c8af4e5472166b02aec7f3f526901ce939094e5861f6d |
| SHA1 | 48be0ec2e8cb90cac2be49ef71e44390a0f648ce |
| MD5 | a216803d691d92acc44ac77d981aa767 |
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 | 80 / 100 |
| Dangerous kernel imports | 100 / 100 |
| IOCTL dispatch surface | 6 / 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-mode APIs resolved from the Import Address Table of WinFlash64.sys, ranked by exploitation relevance.
| API | Risk | Why it matters |
|---|---|---|
| MmMapLockedPages | critical | Highly dangerous - potential for arbitrary code execution, memory corruption, or process termination |
| MmMapIoSpace | critical | Highly dangerous - potential for arbitrary code execution, memory corruption, or process termination |
| MmUnmapIoSpace | medium | Moderate risk - system modification capability |
| KeBugCheckEx | medium | Moderate risk - system modification capability |
| RtlInitUnicodeString | low | Standard kernel API - generally benign |
| IoCreateSymbolicLink | low | Standard kernel API - generally benign |
| ExAllocatePoolWithTag | low | Standard kernel API - generally benign |
| IofCompleteRequest | low | Standard kernel API - generally benign |
| IoDeleteSymbolicLink | low | Standard kernel API - generally benign |
| IoCreateDevice | low | Standard kernel API - generally benign |
| IoDeleteDevice | low | Standard kernel API - generally benign |
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 |
| 0x00808189 | medium | METHOD_IN_DIRECT | FILE_DEVICE_CUSTOM Function #98 |
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 | 0x099A | 0x0A00 | 5.97 | CODE, EXEC, READ |
| .rdata | 0x017C | 0x0200 | 3.33 | IDATA, READ |
| .data | 0x0120 | 0x0200 | 0.3 | IDATA, READ, WRITE |
| .pdata | 0x0078 | 0x0200 | 1.03 | IDATA, READ |
| INIT | 0x0262 | 0x0400 | 3.35 | CODE, EXEC, READ, WRITE, DISCARD |
| Control Flow Guard | Not enabled |
|---|---|
| ASLR | Not enabled |
| DEP | Not enabled |
| Integrity check | Not enforced |
| Mitigation score | 5 / 100 |
| Rule | Severity | Detects |
|---|---|---|
| BYOVD_MemRW | critical | Phys memory mapping + device creation |
| SUSP_PhysMem | high | Physical memory mapping |
Techniques this driver could enable if loaded by an adversary.
| ID | Technique | Tactic |
|---|---|---|
| T1003 | OS Credential Dumping | Credential Access |
| T1003.001 | OS Credential Dumping: LSASS Memory | Credential Access |
| T1006 | Direct Volume Access | Defense Evasion |
| 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 |
| Signer | VeriSign Time Stamping Services CA |
|---|---|
| Signer organisation | VeriSign, Inc. |
| Issuer | Thawte Timestamping CA |
| Serial | 47BF1995DF8D524643F7DB6D480D31A4 |
| Valid from | 2003-12-04 00:00 UTC |
| Valid until | 2013-12-03 23:59 UTC (expired) |
| Signature validity | Not verified |
Engine angr, status completed, 27 paths explored at a maximum depth of 27. Vulnerability classes reached: 1. 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.
Based on DriverShield static and dynamic analysis, WinFlash64.sys is flagged as vulnerable and is a potential Bring Your Own Vulnerable Driver (BYOVD) risk. Its composite risk score is 72/100 (verdict: vulnerable). Always validate findings independently before acting.
WinFlash64.sys has a DriverShield composite risk score of 72/100, placing it in the vulnerable verdict band. SHA256: 316a27e2bdb86222bc7c8af4e5472166b02aec7f3f526901ce939094e5861f6d.
WinFlash64.sys is a Windows kernel-mode driver (.sys) analyzed by DriverShield for vulnerabilities, BYOVD abuse potential, and malware indicators. It is code-signed by VeriSign Time Stamping Services CA.
Related: Other drivers signed by VeriSign Time Stamping Services CA · What an IOCTL dispatch code is · How YARA matching feeds the score · BYOVD research index · full driver database · CVE library · code signing atlas