CVE-2021-3675 [Medium] | Input Validation Bypass in Fingerprint Driver

Improper Input Validation vulnerability in synaTEE.signed.dll of Synaptics Fingerprint Driver allows a local authorized attacker to overwrite a heap tag, with potential loss of confidentiality. This issue affects: Synaptics Synaptics Fingerprint Driver 5.1.xxx.26 versions prior to xxx=340 on x86/64; 5.2.xxxx.26 versions prior to xxxx=3541 on x86/64; 5.2.2xx.26 versions prior to xx=29 on x86/64; 5.2.3xx.26 versions prior to xx=25 on x86/64; 5.3.xxxx.26 versions prior to xxxx=3543 on x86/64; 5.5.xx.1058 versions prior to xx=44 on x86/64; 5.5.xx.1102 versions prior to xx=34 on x86/64; 5.5.xx.1116 versions prior to xx=14 on x86/64; 6.0.xx.1104 versions prior to xx=50 on x86/64; 6.0.xx.1108 versions prior to xx=31 on x86/64; 6.0.xx.1111 versions prior to xx=58 on x86/64.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2025-11-14	0.16%	0.12%	-0.03%
2	2025-11-10	0.04%	0.16%	+0.11%
3	2025-07-19	—	0.04%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2025-11-14

0.16%

0.12%

-0.03%

2025-11-10

0.04%

0.16%

+0.11%

2025-07-19

—

0.04%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
5.5	3.1	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:N) Service keeps running; no real outage angle.	1.8	3.6	[email protected]
7.1	3.1	HIGH	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	5.2	[email protected]
3.6	2.0	LOW	`AV:L/AC:L/Au:N/C:P/I:N/A:P` Click to expand Access vector (AV:L) Requires local access to the target system. Access complexity (AC:L) Exploitation conditions are straightforward and predictable. Authentication (AU:N) No authentication is required. Confidentiality impact (C:P) Partial confidentiality impact. Integrity impact (I:N) No integrity impact. Availability impact (A:P) Partial availability impact.	3.9	4.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

5.5

3.1

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:N): Service keeps running; no real outage angle.

1.8

3.6

[email protected]

7.1

3.1

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

5.2

[email protected]

3.6

2.0

LOW

AV:L/AC:L/Au:N/C:P/I:N/A:P Click to expand

Access vector (AV:L): Requires local access to the target system.
Access complexity (AC:L): Exploitation conditions are straightforward and predictable.
Authentication (AU:N): No authentication is required.
Confidentiality impact (C:P): Partial confidentiality impact.
Integrity impact (I:N): No integrity impact.
Availability impact (A:P): Partial availability impact.

3.9

4.9

[email protected]

Affected software / configurations for CVE-2021-3675

Vendor	Product	Version	Raw CPE
synaptics	fingerprint_driver	>= 5.1.000.26, < 5.1.340.26	cpe:2.3:a:synaptics:fingerprint_driver::::::::
synaptics	fingerprint_driver	>= 5.2.0000.26, < 5.2.3541.26	cpe:2.3:a:synaptics:fingerprint_driver::::::::
synaptics	fingerprint_driver	>= 5.2.200.26, < 5.2.229.26	cpe:2.3:a:synaptics:fingerprint_driver::::::::
synaptics	fingerprint_driver	>= 5.2.300.26, < 5.2.325.26	cpe:2.3:a:synaptics:fingerprint_driver::::::::
synaptics	fingerprint_driver	>= 5.3.0000.26, < 5.3.3543.26	cpe:2.3:a:synaptics:fingerprint_driver::::::::
synaptics	fingerprint_driver	>= 5.5.00.1058, < 5.5.44.1058	cpe:2.3:a:synaptics:fingerprint_driver::::::::
synaptics	fingerprint_driver	>= 5.5.00.1102, < 5.5.34.1102	cpe:2.3:a:synaptics:fingerprint_driver::::::::
synaptics	fingerprint_driver	>= 5.5.00.1116, < 5.5.14.1116	cpe:2.3:a:synaptics:fingerprint_driver::::::::
synaptics	fingerprint_driver	>= 6.0.00.1111, < 6.0.58.1111	cpe:2.3:a:synaptics:fingerprint_driver::::::::

References for CVE-2021-3675

URL	Tags
https://support.hp.com/us-en/document/ish_6411153-6411191-16/hpsbhf03797	Patch Third Party Advisory
https://support.lenovo.com/us/en/product_security/LEN-68054	Third Party Advisory
https://synaptics.com/sites/default/files/2022-06/fingerprint-driver-SGX-security-brief-2022-06-14.pdf	Vendor Advisory

URL

CVE-2021-3675 | synaTEE.signed.dll Out-Of-Bounds Heap Write

Exploit prediction scoring system (EPSS) score for CVE-2021-3675

Common vulnerability scoring system (CVSS) metrics for CVE-2021-3675

Weakness enumeration for CVE-2021-3675

Affected software / configurations for CVE-2021-3675

References for CVE-2021-3675