CVE-2021-1233 | Cisco SD-WAN Information Disclosure Vulnerability

A vulnerability in the CLI of Cisco SD-WAN Software could allow an authenticated, local attacker to access sensitive information on an affected device. The vulnerability is due to insufficient input validation of requests that are sent to the iperf tool. An attacker could exploit this vulnerability by sending a crafted request to the iperf tool, which is included in Cisco SD-WAN Software. A successful exploit could allow the attacker to obtain any file from the filesystem of an affected device.

Published: 2021-01-20 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-1233 is rated Low Risk (26.1/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.32%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-1233

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.05% 0.32% +0.27%
2 2025-03-17 0.04% 0.05% +0.01%
3 2023-03-07 0.04%

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-1233

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.4 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:H/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: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:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
0.8 3.6 [email protected]
4.4 3.0 MEDIUM
CVSS:3.0/AV:L/AC:L/PR:H/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: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:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
0.8 3.6 [email protected]
4.9 2.0 MEDIUM
AV:L/AC:L/Au:N/C:C/I:N/A:N 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:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
3.9 6.9 [email protected]

Weakness enumeration for CVE-2021-1233

Affected software / configurations for CVE-2021-1233

Vendor Product Version Raw CPE
cisco sd-wan_firmware < 18.4.3 cpe:2.3:o:cisco:sd-wan_firmware:*:*:*:*:*:*:*:*
cisco catalyst_sd-wan_manager cpe:2.3:a:cisco:catalyst_sd-wan_manager:-:*:*:*:*:*:*:*
cisco sd-wan_vbond_orchestrator cpe:2.3:a:cisco:sd-wan_vbond_orchestrator:-:*:*:*:*:*:*:*

References for CVE-2021-1233

cvelogic Threat Intelligence