A vulnerability in the process of uploading new application images to Cisco FXOS on the Cisco Firepower 4100 Series Next-Generation Firewall (NGFW) and Firepower 9300 Security Appliance could allow an authenticated, remote attacker using path traversal techniques to create or overwrite arbitrary files on an affected device. The vulnerability is due to insufficient validation during the application image upload process. An attacker could exploit this vulnerability by creating an application image containing malicious code and installing the image on the affected device using the CLI or web-based user interface (web UI). These actions occur prior to signature verification and could allow the attacker to create and execute arbitrary code with root privileges. Note: A missing or invalid signature in the application image will cause the upload process to fail, but does not prevent the exploit. Cisco Bug IDs: CSCvc21901.
Conclusion & alert: CVE-2018-0300 is rated High Risk (66.6/100): CVSS High severity, with high exploitation likelihood (EPSS 7.40%, 94th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +5.57% over the last day, indicating growing attacker interest. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 1.83% | 7.40% | +5.57% |
| 2 | 2026-01-05 | 1.93% | 1.83% | -0.10% |
| 3 | 2025-11-21 | — | 1.93% | — |
Full EPSS history (19 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.2 | 3.0 | HIGH |
|
1.2 | 5.9 | [email protected] |
| 9.0 | 2.0 | HIGH |
|
8.0 | 10.0 | [email protected] |
| URL | Tags |
|---|---|
| http://www.securitytracker.com/id/1041169 | Third Party Advisory VDB Entry |
| https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180620-firepwr-pt | Vendor Advisory |