Is CVE-2020-3134 being actively exploited?

CVE-2020-3134 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2020-3134?

CVE-2020-3134 has a CVSS 3.1 base score of 6.5 (MEDIUM).

CVE-2020-3134

MEDIUM · CVSS 6.5EPSS 1.1%EU EUVD

A vulnerability in the zip decompression engine of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper validation of zip files. An attacker could exploit this vulnerability by sending an email message with a crafted zip-compressed attachment. A successful exploit could trigger a restart of the content-scanning process, causing a temporary DoS condition. This vulnerability affects Cisco AsyncOS Software for Cisco ESA releases earlier than 13.0.

Key facts

CVSS score: 6.5 (v3.1)
Severity: MEDIUM
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Weakness (CWE): CWE-20
EPSS score: 1.1% (65th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2020-24405)
Published: January 26, 2020
NVD last modified: June 17, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2020-24405 in the EU Vulnerability Database. Last updated in EUVD on November 15, 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-dos-87mBkc8n(Vendor Advisory)

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

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