CVE-2020-3179
highpriority · track · 31EPSS 0.020 · 81 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the generic routing encapsulation (GRE) tunnel decapsulation feature of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to a memory handling error when GRE over IPv6 traffic is processed. An attacker could exploit this vulnerability by sending crafted GRE over IPv6 packets with either IPv4 or IPv6 payload through an affected device. A successful exploit could allow the attacker to cause the device to crash, resulting in a DoS condition.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixed6.3.0cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed6.3.0.1cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed6.3.0.2cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed6.3.0.3cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed6.3.0.4cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed6.4.0cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed6.4.0.1cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed6.4.0.2cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed6.4.0.3cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed6.4.0.4cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed6.4.0.5cisco_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⚠ sources disagree · medium–high · 6.9–8.6
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (40)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-ftd-dos-2-sS2h7aWeCisco Firepower Threat Defense Software Generic Routing Encapsulation Tunnel IPv6 Denial of Service Vulnerability2020-05-06csaf · cisco_csafUS
A vulnerability in the generic routing encapsulation (GRE) tunnel decapsulation feature of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to a memory handling error when GRE over IPv6 traffic is processed. An attacker could exploit this vulnerability by sending crafted GRE over IPv6 packets with either IPv4 or IPv6 payload through an affected device. A successful exploit could allow the attacker to cause the device to crash, resulting in a DoS condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is part of the May 2020 Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication, which includes 12 Cisco Security Advisories that describe 12 vulnerabilities. For a complete list of the advisories and links to them, see Cisco Event Response: May 2020 Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-73830"].
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (7)
External citations — patches, advisories, analysis.
- http://www.nsfocus.net/vulndb/47279cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2020-3179cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-dos-2-sS2h7aWecnnvd
- https://www.auscert.org.au/bulletins/ESB-2020.1614.2/cnnvd
- https://www.auscert.org.au/bulletins/ESB-2020.1614/cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-dos-2-sS2h7aWeenisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-dos-2-sS2h7aWeVendor Advisorynvd
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