How severe is CVE-2020-3337?

CVE-2020-3337 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2020-3337 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3337?

CVE-2020-3337 affects Cisco Umbrella. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3337?

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

When was CVE-2020-3337 published?

CVE-2020-3337 was published on 2020-06-18 and last updated on 2026-06-17.

CVE-2020-3337

CVE-2020-3337 is a medium-severity vulnerability in Cisco Umbrella with a CVSS 3.x base score of 6.1. 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-601.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 5.8
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-601
Affected product: Cisco Umbrella
Published: 2020-06-18
Last modified: 2026-06-17

Description

A vulnerability in the web server of Cisco Umbrella could allow an unauthenticated, remote attacker to redirect a user to an undesired web page. The vulnerability is due to improper input validation of the URL parameters in an HTTP request that is sent to an affected device. An attacker could exploit this vulnerability by sending a crafted HTTP request that could cause the web application to redirect the request to a specified malicious URL. A successful exploit could allow the attacker to redirect a user to a malicious website.

Frequently asked questions

What is CVE-2020-3337?: A vulnerability in the web server of Cisco Umbrella could allow an unauthenticated, remote attacker to redirect a user to an undesired web page. The vulnerability is due to improper input validation of the URL parameters in an HTTP request that is sent to an affected device. An attacker could exploit this vulnerability by sending a crafted HTTP request that could cause the web application to redirect the request to a specified malicious URL. A successful exploit could allow the attacker to redirect a user to a malicious website.
How severe is CVE-2020-3337?: CVE-2020-3337 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2020-3337 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3337?: CVE-2020-3337 affects Cisco Umbrella. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3337?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-3337 published?: CVE-2020-3337 was published on 2020-06-18 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-umbrella-open-redire-UgK9dWK4

Affected products (1)

cpe:2.3:a:cisco:umbrella:*:*:*:*:*:*:*:*

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