CVE-2020-0951 [Medium] | Security Bypass in Powershell

A security feature bypass vulnerability exists in Windows Defender Application Control (WDAC) which could allow an attacker to bypass WDAC enforcement. An attacker who successfully exploited this vulnerability could execute PowerShell commands that would be blocked by WDAC. To exploit the vulnerability, an attacker need administrator access on a local machine where PowerShell is running. The attacker could then connect to a PowerShell session and send commands to execute arbitrary code. The update addresses the vulnerability by correcting how PowerShell commands are validated when WDAC protection is enabled.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.53%	7.04%	+6.50%
2	2025-11-21	0.40%	0.53%	+0.14%
3	2025-11-18	—	0.40%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.53%

7.04%

+6.50%

2025-11-21

0.40%

0.53%

+0.14%

2025-11-18

—

0.40%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
6.7	3.1	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/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:H) They need powerful rights—admin, root, or similar—before this pays off. 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:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	0.8	5.9	[email protected]
6.7	3.1	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/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:H) They need powerful rights—admin, root, or similar—before this pays off. 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:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	0.8	5.9	[email protected]
7.2	2.0	HIGH	`AV:L/AC:L/Au:N/C:C/I:C/A:C` 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:C) Complete confidentiality impact. Integrity impact (I:C) Complete integrity impact. Availability impact (A:C) Complete availability impact.	3.9	10.0	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

6.7

3.1

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/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:H): They need powerful rights—admin, root, or similar—before this pays off.
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:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

0.8

5.9

[email protected]

6.7

3.1

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/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:H): They need powerful rights—admin, root, or similar—before this pays off.
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:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

0.8

5.9

[email protected]

7.2

2.0

HIGH

AV:L/AC:L/Au:N/C:C/I:C/A:C 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:C): Complete confidentiality impact.
Integrity impact (I:C): Complete integrity impact.
Availability impact (A:C): Complete availability impact.

3.9

10.0

[email protected]

Affected software / configurations for CVE-2020-0951

Vendor	Product	Version	Raw CPE
microsoft	powershell	>= 7.0, < 7.0.8	cpe:2.3:a:microsoft:powershell::::::::
microsoft	powershell	>= 7.1, < 7.1.5	cpe:2.3:a:microsoft:powershell::::::::
microsoft	powershell	7.0.8	cpe:2.3:a:microsoft:powershell:7.0.8:::::::*
microsoft	windows_10	1607	cpe:2.3:o:microsoft:windows_10:1607::::::x64:
microsoft	windows_10	1607	cpe:2.3:o:microsoft:windows_10:1607::::::x86:
microsoft	windows_10	1709	cpe:2.3:o:microsoft:windows_10:1709:::::::*
microsoft	windows_10	1803	cpe:2.3:o:microsoft:windows_10:1803:::::::*
microsoft	windows_10	1809	cpe:2.3:o:microsoft:windows_10:1809:::::::*
microsoft	windows_10	1903	cpe:2.3:o:microsoft:windows_10:1903:::::::*
microsoft	windows_10	1909	cpe:2.3:o:microsoft:windows_10:1909:::::::*
microsoft	windows_10	2004	cpe:2.3:o:microsoft:windows_10:2004:::::::*
microsoft	windows_server_2016	—	cpe:2.3:o:microsoft:windows_server_2016:-:::::::*
microsoft	windows_server_2016	1903	cpe:2.3:o:microsoft:windows_server_2016:1903:::::::*
microsoft	windows_server_2016	1909	cpe:2.3:o:microsoft:windows_server_2016:1909:::::::*
microsoft	windows_server_2016	2004	cpe:2.3:o:microsoft:windows_server_2016:2004:::::::*
microsoft	windows_server_2019	—	cpe:2.3:o:microsoft:windows_server_2019:-:::::::*

References for CVE-2020-0951

URL	Tags
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0951	Patch Vendor Advisory

URL

CVE-2020-0951 | Windows Defender Application Control Security Feature Bypass Vulnerability

Exploit prediction scoring system (EPSS) score for CVE-2020-0951

Common vulnerability scoring system (CVSS) metrics for CVE-2020-0951

Weakness enumeration for CVE-2020-0951

Affected software / configurations for CVE-2020-0951

References for CVE-2020-0951