How severe is CVE-2020-3375?

CVE-2020-3375 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-3375 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3375?

CVE-2020-3375 primarily affects Cisco Sd-wan. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-3375?

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

When was CVE-2020-3375 published?

CVE-2020-3375 was published on 2020-07-31 and last updated on 2026-06-17.

CVE-2020-3375

CVE-2020-3375 is a critical-severity vulnerability in Cisco Sd-wan with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Sd-wan
Published: 2020-07-31
Last modified: 2026-06-17

Description

A vulnerability in Cisco SD-WAN Solution Software could allow an unauthenticated, remote attacker to cause a buffer overflow on an affected device. The vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending crafted traffic to an affected device. A successful exploit could allow the attacker to gain access to information that they are not authorized to access, make changes to the system that they are not authorized to make, and execute commands on an affected system with privileges of the root user.

Frequently asked questions

What is CVE-2020-3375?: A vulnerability in Cisco SD-WAN Solution Software could allow an unauthenticated, remote attacker to cause a buffer overflow on an affected device. The vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending crafted traffic to an affected device. A successful exploit could allow the attacker to gain access to information that they are not authorized to access, make changes to the system that they are not authorized to make, and execute commands on an affected system with privileges of the root user.
How severe is CVE-2020-3375?: CVE-2020-3375 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-3375 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3375?: CVE-2020-3375 primarily affects Cisco Sd-wan. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-3375?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-3375 published?: CVE-2020-3375 was published on 2020-07-31 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdbufof-h5f5VSeL

Affected products (2)

cpe:2.3:a:cisco:sd-wan:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe_sd-wan:*:*:*:*:*:*:*:*

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