Secure Firewall ASA and FTD
CVE-2026-20295: Cisco Secure Firewall Management Center and Secure Firewall Threat Defense Software sftunnel Memory Exhaustion Denial of Service Vulnerability
A vulnerability in the sftunnel inter-device communication protocol of Cisco Secure FMC Software and Cisco Secure FTD Software could allow an unauthenticated, remote attacker to exhaust the available memory of an affected device.
Published
ExploitedNot in CISA KEV
Ransomware useNot reportedPer CISA
SeverityHIGHCVSS 3.1 8.6
EPSS0.55%Chance of exploitation in 30 days
Public exploitNot tracked
FixNot yet
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.3 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.3 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.3 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.4 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.4 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.4 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.3 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.6 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.4 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.4 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.7 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.4 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.6 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.4 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.6 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.7 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.6 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.7 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.4 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.4 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.6 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.7 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.6 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 10.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.4 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.4 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.0 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.2 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.7 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.6 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 7.4 | See the advisory |
| Cisco Secure Firewall Management Center (FMC) 10.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.3 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.3 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.3 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.4 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.4 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.4 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.3 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.6 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.4 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.4 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.7 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.4 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.6 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.4 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.6 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.7 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.7 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.6 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.7 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.4 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.4 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.6 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 10.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.4 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.0 | See the advisory |
| Cisco Secure Firewall Threat Defense (FTD) Software 7.2 | See the advisory |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
A vulnerability in the sftunnel inter-device communication protocol of Cisco Secure FMC Software and Cisco Secure FTD Software could allow an unauthenticated, remote attacker to exhaust the available memory of an affected device.
This vulnerability is due to improper management of memory resources during sftunnel TLS connection setup. An attacker could exploit this vulnerability by sending crafted sftunnel TLS frames to an affected device during the connection setup. A successful exploit could allow the attacker to exhaust the available memory on the affected device, which could result in a DoS condition.
Exploitation
The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerabilities that are described in this advisory.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 11 Oct 2026.