CVE-2026-20295
published 2026-09-16CVE-2026-20295: A vulnerability in the sftunnel inter-device communication protocol of Cisco Secure FMC Software and Cisco Secure FTD Software could allow an unauthenticated…
PriorityP356high8.6CVSS 3.1
AVNACLPRNUINSCCNINAH
EPSS
0.55%
44.8th percentile
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.
Affected
126 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
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VulDB
Cisco Secure Firewall Management Center sftunnel denial of service
vuldb·2026-09-16·CVSS 8.6
CVE-2026-20295 [HIGH] Cisco Secure Firewall Management Center sftunnel denial of service
A vulnerability classified as critical was found in Cisco Secure Firewall Management Center and Secure Firewall Threat Defense Software. This affects an unknown part of the component sftunnel. Executing a manipulation can lead to denial of service.
This vulnerability is registered as CVE-2026-20295. It is possible to launch the attack remotely. No exploit is available.
Upgrading the affected component is advised.
GHSA
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
ghsa_unreviewed·2026-09-16
CVE-2026-20295 [HIGH] CWE-789 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
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.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-09-16
Published