How severe is CVE-2021-1233?

CVE-2021-1233 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-1233 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1233?

CVE-2021-1233 primarily affects Cisco Sd-wan Firmware. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-1233?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-1233 published?

CVE-2021-1233 was published on 2021-01-20 and last updated on 2026-06-17.

CVE-2021-1233

CVE-2021-1233 is a medium-severity vulnerability in Cisco Sd-wan Firmware with a CVSS 3.x base score of 4.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 4.4)
CVSS v2: 4.9
EPSS exploit prediction: 0% (24th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Sd-wan Firmware
Published: 2021-01-20
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2021-1233?: 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.
How severe is CVE-2021-1233?: CVE-2021-1233 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-1233 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1233?: CVE-2021-1233 primarily affects Cisco Sd-wan Firmware. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-1233?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-1233 published?: CVE-2021-1233 was published on 2021-01-20 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-infodis-2-UPO232DG

Affected products (3)

cpe:2.3:o:cisco:sd-wan_firmware:*:*:*:*:*:*:*:*
cpe:2.3:a:cisco:catalyst_sd-wan_manager:-:*:*:*:*:*:*:*
cpe:2.3:a:cisco:sd-wan_vbond_orchestrator:-:*:*:*:*:*:*:*

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