Is CVE-2020-3133 being actively exploited?

CVE-2020-3133 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2020-3133?

CVE-2020-3133 has a CVSS 3.1 base score of 7.5 (HIGH).

CVE-2020-3133

HIGH · CVSS 7.5EPSS 1.4%EU EUVD

A vulnerability in the email message scanning of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured filters on the device. The vulnerability is due to improper validation of incoming emails. An attacker could exploit this vulnerability by sending a crafted email message to a recipient protected by the ESA. A successful exploit could allow the attacker to bypass the configured content filters, which could allow malicious content to pass through the device.

Key facts

CVSS score: 7.5 (v3.1)
Severity: HIGH
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Weakness (CWE): CWE-20
EPSS score: 1.4% (72th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2020-24404)
Published: September 23, 2020
NVD last modified: June 17, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2020-24404 in the EU Vulnerability Database. Last updated in EUVD on November 13, 2024.

View on the EU Vulnerability Database

Affected products

cisco / email security appliance

Certified products that may be affected

3 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

Cisco Email Security Appliance 9.8 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-10798-2017 - archived
Cisco Email Security Appliance v9.1 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-10631-2015 - archived
IronPort Email Security Appliances (ESA), comprising the C160, C370, X1060, and X1070 appliance models, running IronPort AsyncOS software, version 7.1, and the C670 appliance model running IronPort AsyncOS version 7.3 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-10438-2010 - archived

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-bypass-5Cdv2HMA(Vendor Advisory)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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