CVE-2019-12655
highpriority · track · 31EPSS 0.020 · 80 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the FTP application layer gateway (ALG) functionality used by Network Address Translation (NAT), NAT IPv6 to IPv4 (NAT64), and the Zone-Based Policy Firewall (ZBFW) in Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a buffer overflow that occurs when an affected device inspects certain FTP traffic. An attacker could exploit this vulnerability by performing a specific FTP transfer through the device. A successful exploit could allow the attacker to cause the device to reload.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixed16.10.1cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.1acisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.1bcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.1ccisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.1dcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.1ecisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.1scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.3.7cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.6.4cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.6.4acisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.6.4scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.6.5cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.6.5acisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.6.5bcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.9.1cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.9.1acisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.9.1bcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.9.1ccisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.9.1dcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.9.1scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.9.2cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.9.2acisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.9.2scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed17.11.99SWcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.16.8Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.16.9Scisco_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 (38)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-20190925-ftpCisco IOS XE Software FTP Application Layer Gateway for NAT, NAT64, and ZBFW Denial of Service Vulnerability2019-09-25csaf · cisco_csafUS
A vulnerability in the FTP application layer gateway (ALG) functionality used by Network Address Translation (NAT), NAT IPv6 to IPv4 (NAT64), and the Zone-Based Policy Firewall (ZBFW) in Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a buffer overflow that occurs when an affected device inspects certain FTP traffic. An attacker could exploit this vulnerability by performing a specific FTP transfer through the device. A successful exploit could allow the attacker to cause the device to reload. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-ftp ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-ftp"] This advisory is part of the September 25, 2019, release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication, which includes 12 Cisco Security Advisories that describe 13 vulnerabilities. For a complete list of the advisories and links to them, see Cisco Event Response: September 2019 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-72547"].
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (22)
External citations — patches, advisories, analysis.
- https://nvd.nist.gov/vuln/detail/CVE-2019-12655cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-awrcnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-ctspac-doscnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-dtcnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-ftpcnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-iosxe-codeexeccnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-iosxe-ctbypasscnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-iosxe-digsig-bypasscnnvd
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