How severe is CVE-2020-3387?

CVE-2020-3387 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-3387 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 14% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3387?

CVE-2020-3387 affects Cisco Sd-wan Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3387?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-3387 published?

CVE-2020-3387 was published on 2020-07-16 and last updated on 2026-06-17.

CVE-2020-3387

CVE-2020-3387 is a high-severity vulnerability in Cisco Sd-wan Firmware with a CVSS 3.x base score of 8.8. Its EPSS exploit-prediction score of 14% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 14% (96th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Sd-wan Firmware
Published: 2020-07-16
Last modified: 2026-06-17

Description

A vulnerability in Cisco SD-WAN vManage Software could allow an authenticated, remote attacker to execute code with root privileges on an affected system. The vulnerability is due to insufficient input sanitization during user authentication processing. An attacker could exploit this vulnerability by sending a crafted response to the Cisco SD-WAN vManage Software. A successful exploit could allow the attacker to access the software and execute commands they should not be authorized to execute.

Frequently asked questions

What is CVE-2020-3387?: A vulnerability in Cisco SD-WAN vManage Software could allow an authenticated, remote attacker to execute code with root privileges on an affected system. The vulnerability is due to insufficient input sanitization during user authentication processing. An attacker could exploit this vulnerability by sending a crafted response to the Cisco SD-WAN vManage Software. A successful exploit could allow the attacker to access the software and execute commands they should not be authorized to execute.
How severe is CVE-2020-3387?: CVE-2020-3387 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-3387 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 14% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3387?: CVE-2020-3387 affects Cisco Sd-wan Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3387?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-3387 published?: CVE-2020-3387 was published on 2020-07-16 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:cisco:sd-wan_firmware:*:*:*:*:*:*:*:*

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