CVE-2021-1589 [Medium] | Security Vulnerability in Sd-Wan

A vulnerability in the disaster recovery feature of Cisco SD-WAN vManage Software could allow an authenticated, remote attacker to gain unauthorized access to user credentials. This vulnerability exists because access to API endpoints is not properly restricted. An attacker could exploit this vulnerability by sending a request to an API endpoint. A successful exploit could allow the attacker to gain unauthorized access to administrative credentials that could be used in further attacks.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.24%	0.94%	+0.70%
2	2025-10-22	0.36%	0.24%	-0.12%
3	2025-03-30	—	0.36%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.24%

0.94%

+0.70%

2025-10-22

0.36%

0.24%

-0.12%

2025-03-30

—

0.36%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
6.5	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. 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.	2.8	3.6	[email protected]
6.5	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. 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.	2.8	3.6	[email protected]
3.5	2.0	LOW	`AV:N/AC:M/Au:S/C:P/I:N/A:N` Click to expand Access vector (AV:N) Can be exploited remotely over network reachability. Access complexity (AC:M) Exploitation needs some favorable conditions, but not exceptional ones. Authentication (AU:S) A single authentication is required. Confidentiality impact (C:P) Partial confidentiality impact. Integrity impact (I:N) No integrity impact. Availability impact (A:N) No availability impact.	6.8	2.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

6.5

3.1

MEDIUM

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

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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.

2.8

3.6

[email protected]

6.5

3.1

MEDIUM

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

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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.

2.8

3.6

[email protected]

3.5

2.0

LOW

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

Access vector (AV:N): Can be exploited remotely over network reachability.
Access complexity (AC:M): Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S): A single authentication is required.
Confidentiality impact (C:P): Partial confidentiality impact.
Integrity impact (I:N): No integrity impact.
Availability impact (A:N): No availability impact.

6.8

2.9

[email protected]

Affected software / configurations for CVE-2021-1589

Vendor	Product	Version	Raw CPE
cisco	sd-wan	>= 20.3, < 20.3.4	cpe:2.3:a:cisco:sd-wan::::::::
cisco	sd-wan	>= 20.4, < 20.4.2	cpe:2.3:a:cisco:sd-wan::::::::
cisco	sd-wan	>= 20.5, < 20.5.2	cpe:2.3:a:cisco:sd-wan::::::::
cisco	sd-wan	>= 20.6, < 20.6.1	cpe:2.3:a:cisco:sd-wan::::::::

References for CVE-2021-1589

URL	Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sd-wan-credentials-ydYfskzZ	Patch Vendor Advisory

URL

CVE-2021-1589 | Cisco SD-WAN vManage Software Disaster Recovery Feature Password Exposure Vulnerability

Exploit prediction scoring system (EPSS) score for CVE-2021-1589

Common vulnerability scoring system (CVSS) metrics for CVE-2021-1589

Weakness enumeration for CVE-2021-1589

Affected software / configurations for CVE-2021-1589

References for CVE-2021-1589