How severe is CVE-2020-3521?

CVE-2020-3521 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2020-3521 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3521?

CVE-2020-3521 affects Cisco Data Center Network Manager. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3521?

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

When was CVE-2020-3521 published?

CVE-2020-3521 was published on 2020-08-26 and last updated on 2026-06-17.

CVE-2020-3521

CVE-2020-3521 is a medium-severity vulnerability in Cisco Data Center Network Manager with a CVSS 3.x base score of 5.3. 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 5.3)
CVSS v2: 4.0
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Data Center Network Manager
Published: 2020-08-26
Last modified: 2026-06-17

Description

A vulnerability in a specific REST API of Cisco Data Center Network Manager (DCNM) Software could allow an authenticated, remote attacker to conduct directory traversal attacks on an affected device. The vulnerability is due to insufficient validation of user-supplied input to the API. An attacker with a low-privileged account could exploit this vulnerability by sending a crafted request to the API. A successful exploit could allow the attacker to read arbitrary files on the affected system.

Frequently asked questions

What is CVE-2020-3521?: A vulnerability in a specific REST API of Cisco Data Center Network Manager (DCNM) Software could allow an authenticated, remote attacker to conduct directory traversal attacks on an affected device. The vulnerability is due to insufficient validation of user-supplied input to the API. An attacker with a low-privileged account could exploit this vulnerability by sending a crafted request to the API. A successful exploit could allow the attacker to read arbitrary files on the affected system.
How severe is CVE-2020-3521?: CVE-2020-3521 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-3521 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3521?: CVE-2020-3521 affects Cisco Data Center Network Manager. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3521?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-3521 published?: CVE-2020-3521 was published on 2020-08-26 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-dcnm-file-path-6PKONjHe

Affected products (1)

cpe:2.3:a:cisco:data_center_network_manager:*:*:*:*:*:*:*:*

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