CVE-2026-20324 Cisco Secure Firewall Management Center sftunnel Root Arbitrary Code Exectution Vulnerability
Authenticated attackers can execute arbitrary commands as root by exploiting incorrect permissions in the sftunnel protocol of Cisco FMC.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-20324?
CVE-2026-20324 is a critical missing authorization vulnerability in Cisco Secure Firewall Management Center (FMC), published on 16 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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
Which versions are affected by CVE-2026-20324?
How do I fix CVE-2026-20324?
No fix has been published for CVE-2026-20324 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-20324 being exploited?
There is no known exploitation of CVE-2026-20324 in the wild and no public exploit code.
Sources
Also known as GHSA-m3pq-vq89-c8m5.