speedfan.sys - Vulnerable (78/100) - DriverShield Analysis

Analysis of speedfan.sys: vulnerable verdict, risk score 78/100. 3 YARA matches, 4/75 multi-engine detections. SHA256 22be050955347661. Kernel imports, IOCTL codes, MITRE ATT&CK, and code-signing details.

speedfan.sys - Analysis Report

DriverShield analyzed the Windows kernel driver speedfan.sys and assigned a verdict of Vulnerable with a composite risk score of 78/100, indicating a known or likely vulnerability surface (60-79 band).

Verdict	Vulnerable (78/100)
YARA matches	3
Multi-engine detections	4 / 75
File size	14104 bytes
Code-signing signer	VeriSign Time Stamping Services CA
Analyzed	2026-08-15
SHA256	22be050955347661685a4343c51f11c7811674e030386d2264cd12ecbf544b7c
SHA1	bfe55cacc7c56c9f7bd75bdb4b352c0b745d071b
MD5	5f9785e7535f8f602cb294a54962c9e7

Driver identity

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

File description	SpeedFan Device Driver
Product	Windows (R) Server 2003 DDK driver
Company	Windows (R) Server 2003 DDK provider
Original filename	speedfan.sys
Internal name	speedfan.sys
File version	5.2.3790.0 built by: WinDDK
Copyright	© Microsoft Corporation. All rights reserved.

How the 78/100 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	85 / 100
Dangerous kernel imports	96 / 100
IOCTL dispatch surface	12 / 100
Known-vulnerable corpus	100 / 100
Code-signing state	80 / 100
Packing and entropy	0 / 100
Dynamic behaviour	0 / 100
CVE cross-reference	40 / 100

Kernel imports (9)

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

API	Risk	Why it matters
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
IoDeleteSymbolicLink	low	Standard kernel API - generally benign
IoCreateDevice	low	Standard kernel API - generally benign
IoCreateSymbolicLink	low	Standard kernel API - generally benign
IoDeleteDevice	low	Standard kernel API - generally benign
RtlInitUnicodeString	low	Standard kernel API - generally benign
IofCompleteRequest	low	Standard kernel API - generally benign

IOCTL dispatch codes (4)

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
0x9C40B941	medium	METHOD_IN_DIRECT	CUSTOM_LENOVO Function #3664
0x0080249C	medium	METHOD_BUFFERED	FILE_DEVICE_CUSTOM Function #2343
0x0034039C	medium	METHOD_BUFFERED	FILE_DEVICE_DISK Function #231

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	0x0B42	0x0C00	5.84	CODE, EXEC, READ
.rdata	0x0168	0x0200	3.57	IDATA, READ
.data	0x0110	0x0200	0.3	IDATA, READ, WRITE
.pdata	0x003C	0x0200	0.56	IDATA, READ
INIT	0x01D8	0x0200	4.54	CODE, EXEC, READ, WRITE, DISCARD
.rsrc	0x0400	0x0400	3.36	IDATA, READ, 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.

YARA rule matches (3)

Rule	Severity	Detects
PUA_VULN_Driver_Windowsrserverddkprovider_Speedfansys_Windowsrserverddkdriver_22BE	medium	Detects vulnerable driver mentioned in known-vulnerable driver corpus project using VersionInfo values from the PE header - speedfan.sys. Investigate matches in context: expected filenames or standard...
BYOVD_MemRW	critical	Phys memory mapping + device creation
SUSP_PhysMem	high	Physical memory mapping

MITRE ATT&CK techniques (10)

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
T1543.003	Windows Service	Persistence
T1562.001	Impair Defenses	Defense Evasion
T1569.002	Service Execution	Execution
T1652	Device Driver Discovery	Discovery

Code-signing chain

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

Certificate revision: 0x0200
Certificate type: PKCS#7
Chain: VeriSign Time Stamping Services Signer
Chain: VeriSign Class 3 Code Signing 2004 CA
Chain: Sokno S.R.L.

Associated CVEs

CVE-2007-5633 - SpeedFan driver - allows local users to read/write kernel memory

Symbolic execution

Engine angr, status completed, 22 paths explored at a maximum depth of 22. 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.

Frequently asked questions about speedfan.sys

Is speedfan.sys safe?

Based on DriverShield static and dynamic analysis, speedfan.sys is flagged as vulnerable and is a potential Bring Your Own Vulnerable Driver (BYOVD) risk. Its composite risk score is 78/100 (verdict: vulnerable). Always validate findings independently before acting.

What is the risk score of speedfan.sys?

speedfan.sys has a DriverShield composite risk score of 78/100, placing it in the vulnerable verdict band. SHA256: 22be050955347661685a4343c51f11c7811674e030386d2264cd12ecbf544b7c.

What is speedfan.sys?

speedfan.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.