{"cve":"CVE-2021-1256","nvd":{"published":"2021-04-29T18:15:08.840","modified":"2026-08-11T19:37:30.880","status":"Modified","description":"A vulnerability in the CLI of Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, local attacker to overwrite files on the file system of an affected device by using directory traversal techniques. A successful exploit could cause system instability if important system files are overwritten. This vulnerability is due to insufficient validation of user input for the file path in a specific CLI command. An attacker could exploit this vulnerability by logging in to a targeted device and issuing a specific CLI command with crafted user input. A successful exploit could allow the attacker to overwrite arbitrary files on the file system of the affected device. The attacker would need valid user credentials on the device.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H","score":6.0},"cwes":["CWE-22","CWE-552"],"references":["https://kc.mcafee.com/corporate/index?page=content&id=SB10382","https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-file-overwrite-XknRjGdB","https://kc.mcafee.com/corporate/index?page=content&id=SB10382","https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-file-overwrite-XknRjGdB"],"products":["cisco:secure_firewall_threat_defense"],"source":"nvd","synced_at":"2026-10-19T21:18:09.669877188+00:00"},"epss":{"cve":"CVE-2021-1256","score":0.00501,"percentile":0.42955,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}