CVE-2020-3134

mediumpriority · track · 26EPSS 0.011 · 65 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.09% (65th) EPSS

CVSS 6.4 · medium

Is it mine?

7 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-27

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.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedCisco Email Security Appliance (ESA)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.06.4mediumAV:N/AC:L/Au:N/C:N/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 4.9

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Lprimary · NVD / NIST USexploitability 3.9 · impact 2.5

v3.06.5mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Lsecondary · ENISA EU

v3.06.5mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Lsecondary · psirt@cisco.com USexploitability 3.9 · impact 2.5

v3.06.5mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Lsecondary · Cisco PSIRT US

v3.16.5mediumAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Lsecondary · FSTEC (BDU) RU

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimaryCWE-20US

affected products (7)

Products and version ranges known to be affected.

Cisco Cisco Email Security Appliance (ESA)all versionscisco_csafUS
Cisco Cisco Email Security Appliance (ESA)≤ earlier than 13.0enisa_euvdEU
Cisco Systems Inc. Cisco Email Security Appliances≤ 13.0.0-226fstec_bduRU
Cisco Systems Inc. Cisco Email Security Appliances≤ 12.1-091fstec_bduRU
Cisco Systems Inc. Cisco Email Security Appliances≤ 12.1-071fstec_bduRU
Cisco Systems Inc. Cisco Email Security Appliances≤ 11.1.8-076fstec_bduRU
cisco email security appliance< 13.0nvdUScpe:2.3:a:cisco:email_security_appliance:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

cisco-sa-esa-dos-87mBkc8nCisco Email Security Appliance Zip Decompression Engine Denial of Service Vulnerability2020-01-22csaf · cisco_csafUS
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. Cisco has released software updates that address the vulnerability described in this advisory. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-dos-87mBkc8n ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-dos-87mBkc8n"]

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cisco_csaf nvd NVD CVE.org MITRE

published 2020-01-26modified 2026-06-17

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+25171 more

references (8)

External citations — patches, advisories, analysis.

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