How severe is CVE-2020-3370?

CVE-2020-3370 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2020-3370 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3370?

CVE-2020-3370 affects Cisco Email Security Appliance. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3370?

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

When was CVE-2020-3370 published?

CVE-2020-3370 was published on 2020-07-16 and last updated on 2026-06-17.

CVE-2020-3370

CVE-2020-3370 is a medium-severity vulnerability in Cisco Email Security Appliance with a CVSS 3.x base score of 5.8. 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: Medium (CVSS 3.x base score 5.8)
CVSS v2: 5.0
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Email Security Appliance
Published: 2020-07-16
Last modified: 2026-06-17

Description

A vulnerability in URL filtering of Cisco Content Security Management Appliance (SMA) could allow an unauthenticated, remote attacker to bypass URL filtering on an affected device. The vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending a crafted, malicious HTTP request to an affected device. A successful exploit could allow the attacker to redirect users to malicious sites.

Frequently asked questions

What is CVE-2020-3370?: A vulnerability in URL filtering of Cisco Content Security Management Appliance (SMA) could allow an unauthenticated, remote attacker to bypass URL filtering on an affected device. The vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending a crafted, malicious HTTP request to an affected device. A successful exploit could allow the attacker to redirect users to malicious sites.
How severe is CVE-2020-3370?: CVE-2020-3370 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2020-3370 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3370?: CVE-2020-3370 affects Cisco Email Security Appliance. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3370?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-3370 published?: CVE-2020-3370 was published on 2020-07-16 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ESA-filt-39jXvMfM

Affected products (1)

cpe:2.3:a:cisco:email_security_appliance:*:*:*:*:*:*:*:*

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