CVE-2020-3562
highpriority · track · 35EPSS 0.018 · 79 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the SSL/TLS inspection of Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series firewalls could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper input validation for certain fields of specific SSL/TLS messages. An attacker could exploit this vulnerability by sending a malformed SSL/TLS message through an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. No manual intervention is needed to recover the device after it has reloaded.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco Secure Firewall Threat Defense (FTD) Software 6.4.0 when installed on Cisco Firepower 2100 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Threat Defense (FTD) Software 6.4.0.1 when installed on Cisco Firepower 2100 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Threat Defense (FTD) Software 6.4.0.2 when installed on Cisco Firepower 2100 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Threat Defense (FTD) Software 6.4.0.3 when installed on Cisco Firepower 2100 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Threat Defense (FTD) Software 6.4.0.4 when installed on Cisco Firepower 2100 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Threat Defense (FTD) Software 6.4.0.5 when installed on Cisco Firepower 2100 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Threat Defense (FTD) Software 6.4.0.6 when installed on Cisco Firepower 2100 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Threat Defense (FTD) Software 6.4.0.7 when installed on Cisco Firepower 2100 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Threat Defense (FTD) Software 6.4.0.8 when installed on Cisco Firepower 2100 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Threat Defense (FTD) Software 6.4.0.9 when installed on Cisco Firepower 2100 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (17)
Products and version ranges known to be affected.
- cisco secure firewall threat defense= 6.3.0nvdUScpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*
- cisco secure firewall threat defense= 6.4.0nvdUScpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*
- cisco secure firewall threat defense= 6.5.0nvdUScpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-ftd-ssl-dcrpt-dos-RYEkX4yyCisco Firepower 2100 Series SSL/TLS Inspection Denial of Service Vulnerability2020-10-21csaf · cisco_csafUS
A vulnerability in the SSL/TLS inspection of Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series firewalls could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper input validation for certain fields of specific SSL/TLS messages. An attacker could exploit this vulnerability by sending a malformed SSL/TLS message through an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. No manual intervention is needed to recover the device after it has reloaded. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is part of the October 2020 Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication, which includes 17 Cisco Security Advisories that describe 17 vulnerabilities. For a complete list of the advisories and links to them, see Cisco Event Response: October 2020 Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74302"].
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- http://www.nsfocus.net/vulndb/50192cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2020-3562cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-ssl-dcrpt-dos-RYEkX4yycnnvd
- https://www.auscert.org.au/bulletins/ESB-2020.3646/cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-ssl-dcrpt-dos-RYEkX4yyenisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-ssl-dcrpt-dos-RYEkX4yyVendor Advisorynvd
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