CVE-2026-20324
Cisco Secure Firewall Management Center sftunnel Root Arbitrary Code Exectution Vulnerability
Description
A vulnerability in the sftunnel inter-device communication protocol of Cisco Secure Firewall Management Center (FMC) Software could allow an authenticated, remote attacker to execute arbitrary commands as root. This vulnerability exists because a registered sftunnel peer has incorrect permissions to write an arbitrary file to any location on the device. An attacker could exploit this vulnerability by hijacking the sftunnel communication connection or being a valid registered sftunnel peer and sending an sftunnel command to write a malicious file to the disk of an affected device. A successful exploit could allow the attacker to write a file to the device that is executed with root privileges. To exploit this vulnerability, the attacker must have valid user credentials on the affected device.
Weakness: CWE-862
Affected products
| Vendor | Product | Category | Matched by |
|---|---|---|---|
| Cisco | Cisco Secure Firewall Management Center Check your version | Network & Security Management | cna-assigner |
Vendor-reported products (1)
- Cisco · Cisco Secure Firewall Management Center (FMC)
Vendor advisory
cisco-sa-fmc-sftunn-codex-c3O4Jft2
Cisco Secure Firewall Management Center Software sftunnel Root Arbitrary Code Execution Vulnerability
Cisco’s rating: Critical (advisory CVSS 9.9) · Published Sep 16, 2026
Bug ID: CSCwu14331
The vendor’s rating applies to the whole advisory and can differ from this CVE’s own CVSS severity. Where this comes from