Status: KEV | Advisory ID: CVE-2026-20079
| CVE | CVE-2026-20079 |
| CVSS | CVSS 10.0 (Critical). |
| Affected products | Cisco Secure Firewall Management Center (FMC) and Security Cloud Control (SCC) Firewall Management and Cisco Secure Firewall Management Center |
| Exploitation status | In August 2026, the Cisco PSIRT became aware of active exploitation of this vulnerability. |
| Classified as | CWE-288 (Authentication Bypass Using an Alternate Path or Channel) |
| KEV listing | Added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2026-09-09. |
| Exploitation prediction (EPSS) | 76% probability of exploitation in the next 30 days (99% percentile) -- FIRST.org's EPSS model. |
| Federal remediation deadline | 2026-09-12 (CISA KEV, Binding Operational Directive). |
A vulnerability in the web interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to bypass authentication and execute script files on an affected device to obtain root access to the underlying operating system.
This vulnerability is due to an improper system process that is created at boot time. An attacker could exploit this vulnerability by sending crafted HTTP requests to an affected device. A successful exploit could allow the attacker to execute a variety of scripts and commands that allow root access to the device.
Workarounds: No workarounds available. Cisco strongly recommends that customers upgrade to the fixed software indicated in this advisory.
| Source | Reference |
|---|---|
| NVD | https://nvd.nist.gov/vuln/detail/CVE-2026-20079 |
| Vendor advisory | https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-onprem-fmc-authbypass-5JPp45V2 |