CVE-2021-1432 [High] | Input Validation Bypass in Ios Xe

A vulnerability in the CLI of Cisco IOS XE SD-WAN Software could allow an authenticated, local attacker to execute arbitrary commands on the underlying operating system as the root user. The attacker must be authenticated on the affected device as a low-privileged user to exploit this vulnerability. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by injecting arbitrary commands to a file as a lower-privileged user. The commands are then executed on the device by the root user. A successful exploit could allow the attacker to execute arbitrary commands as the root user.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.08%	0.34%	+0.26%
2	2025-03-30	0.15%	0.08%	-0.07%
3	2025-03-29	—	0.15%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.08%

0.34%

+0.26%

2025-03-30

0.15%

0.08%

-0.07%

2025-03-29

—

0.15%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.3	3.1	HIGH	`CVSS:3.1/AV:L/AC:L/PR:L/UI:R/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:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:R) A real person has to do something—click, install, enable—otherwise it doesn’t land. 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.	1.3	5.9	[email protected]
7.3	3.1	HIGH	`CVSS:3.1/AV:L/AC:L/PR:L/UI:R/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:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:R) A real person has to do something—click, install, enable—otherwise it doesn’t land. 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.	1.3	5.9	[email protected]
6.9	2.0	MEDIUM	`AV:L/AC:M/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:M) Exploitation needs some favorable conditions, but not exceptional ones. 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.	3.4	10.0	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.3

3.1

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:R/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:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:R): A real person has to do something—click, install, enable—otherwise it doesn’t land.
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.

1.3

5.9

[email protected]

7.3

3.1

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:R/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:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:R): A real person has to do something—click, install, enable—otherwise it doesn’t land.
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.

1.3

5.9

[email protected]

6.9

2.0

MEDIUM

AV:L/AC:M/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:M): Exploitation needs some favorable conditions, but not exceptional ones.
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.

3.4

10.0

[email protected]

Affected software / configurations for CVE-2021-1432

Vendor	Product	Version	Raw CPE
cisco	ios_xe	3.15.1xbs	cpe:2.3:o:cisco:ios_xe:3.15.1xbs:::::::*
cisco	ios_xe	3.15.2xbs	cpe:2.3:o:cisco:ios_xe:3.15.2xbs:::::::*
cisco	ios_xe	16.12.1	cpe:2.3:o:cisco:ios_xe:16.12.1:::::::*
cisco	ios_xe	16.12.1a	cpe:2.3:o:cisco:ios_xe:16.12.1a:::::::*
cisco	ios_xe	16.12.1c	cpe:2.3:o:cisco:ios_xe:16.12.1c:::::::*
cisco	ios_xe	16.12.1s	cpe:2.3:o:cisco:ios_xe:16.12.1s:::::::*
cisco	ios_xe	16.12.1t	cpe:2.3:o:cisco:ios_xe:16.12.1t:::::::*
cisco	ios_xe	16.12.1w	cpe:2.3:o:cisco:ios_xe:16.12.1w:::::::*
cisco	ios_xe	16.12.1x	cpe:2.3:o:cisco:ios_xe:16.12.1x:::::::*
cisco	ios_xe	16.12.1y	cpe:2.3:o:cisco:ios_xe:16.12.1y:::::::*
cisco	ios_xe	16.12.1z	cpe:2.3:o:cisco:ios_xe:16.12.1z:::::::*
cisco	ios_xe	16.12.1za	cpe:2.3:o:cisco:ios_xe:16.12.1za:::::::*
cisco	ios_xe	16.12.2	cpe:2.3:o:cisco:ios_xe:16.12.2:::::::*
cisco	ios_xe	16.12.2a	cpe:2.3:o:cisco:ios_xe:16.12.2a:::::::*
cisco	ios_xe	16.12.2s	cpe:2.3:o:cisco:ios_xe:16.12.2s:::::::*
cisco	ios_xe	16.12.2t	cpe:2.3:o:cisco:ios_xe:16.12.2t:::::::*
cisco	ios_xe	16.12.3	cpe:2.3:o:cisco:ios_xe:16.12.3:::::::*
cisco	ios_xe	16.12.3a	cpe:2.3:o:cisco:ios_xe:16.12.3a:::::::*
cisco	ios_xe	16.12.3s	cpe:2.3:o:cisco:ios_xe:16.12.3s:::::::*
cisco	ios_xe	16.12.4	cpe:2.3:o:cisco:ios_xe:16.12.4:::::::*
cisco	ios_xe	16.12.4a	cpe:2.3:o:cisco:ios_xe:16.12.4a:::::::*
cisco	ios_xe	17.2.1	cpe:2.3:o:cisco:ios_xe:17.2.1:::::::*
cisco	ios_xe	17.2.1a	cpe:2.3:o:cisco:ios_xe:17.2.1a:::::::*
cisco	ios_xe	17.2.1r	cpe:2.3:o:cisco:ios_xe:17.2.1r:::::::*
cisco	ios_xe	17.2.1v	cpe:2.3:o:cisco:ios_xe:17.2.1v:::::::*
cisco	ios_xe_sd-wan	—	cpe:2.3:o:cisco:ios_xe_sd-wan::::::::

References for CVE-2021-1432

URL	Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-sdwarbcmdexec-sspOMUr3	Vendor Advisory

URL

CVE-2021-1432 | Cisco IOS XE SD-WAN Software Arbitrary Command Execution Vulnerability

Exploit prediction scoring system (EPSS) score for CVE-2021-1432

Common vulnerability scoring system (CVSS) metrics for CVE-2021-1432

Weakness enumeration for CVE-2021-1432

Affected software / configurations for CVE-2021-1432

References for CVE-2021-1432