{"id":"CVE-2019-12655","aliases":["EUVD-2019-4246","GHSA-56j6-c5p2-5rq5"],"status":"published","title":"Cisco IOS XE Software FTP Application Layer Gateway for NAT, NAT64, and ZBFW Denial of Service Vulnerability","description":"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.","severity":{"version":"3.0","score":8.6,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.01973,"percentile":0.80611,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-120","CWE-20"],"published":"2019-09-25T20:15:33Z","modified":"2026-06-17T02:15:09Z","products":[{"vendor":"cisco","product":"cisco ios xe software 3.16.8s"},{"vendor":"cisco","product":"ios"}],"references":[{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-ftp","tags":["vendor-advisory","x_refsource_CISCO","x_transferred","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2019-12655"},{"url":"https://github.com/advisories/GHSA-56j6-c5p2-5rq5"}],"sources":{"cve":[{"id":"CVE-2019-12655","title":"Cisco IOS XE Software FTP Application Layer Gateway for NAT, NAT64, and ZBFW Denial of Service Vulnerability","description":"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.","status":"published","published":"2019-09-25T20:15:33.502Z","modified":"2024-11-19T18:56:10.689Z","cvss":[{"version":"3.0","score":8.6,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:20:23.697579Z"}],"euvd":[{"id":"EUVD-2019-4246","description":"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.","status":"published","published":"2019-09-25T20:15:33Z","modified":"2024-11-19T18:56:10Z","cvss":[{"version":"3.0","score":8.6,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-03T00:04:55.637912Z"}],"ghsa":[{"id":"GHSA-56j6-c5p2-5rq5","title":"A vulnerability in the FTP application layer gateway (ALG) functionality used by Network Address...","description":"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.","status":"published","published":"2022-05-24T16:56:48Z","modified":"2024-04-04T01:59:58Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-20","CWE-120"],"updated_at":"2026-11-02T14:56:05.019773Z"}],"nvd":[{"id":"CVE-2019-12655","description":"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.","status":"published","published":"2019-09-25T21:15:10.78Z","modified":"2026-06-17T02:15:09.003Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"3.0","score":8.6,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"high","assessor":"secondary"},{"version":"2.0","score":7.8,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:C","level":"high","assessor":"primary"}],"cwes":["CWE-20","CWE-120"],"updated_at":"2026-11-02T14:05:30.039477Z"}]}}