Search/CVE-2026-20324
CVE — Critical

CVE-2026-20324

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…

CVSS v3.1
9.9 CRITICAL
EPSS
%
probability of exploitation in 30 days
CISA KEV
Not listed
no confirmed exploitation reported
News coverage
1
sources referencing this CVE
CVSS v3.1 Detail
Attack VectorNETWORK
Attack ComplexityLOW
Privileges RequiredLOW
User InteractionNONE
ScopeCHANGED
ConfidentialityHIGH
IntegrityHIGH
AvailabilityHIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Connections
2 relationships
Timeline
disclosure → media coverage
Sep 16, 2026
Disclosure — published as a CVE record.
Sep 17, 2026
thehackernews.com reports: Cisco Warns of New Zero-Day ISE Auth Bypass (CVSS 10.0) Exploited in Active Attacks