CVE-2026-20295 is a vulnerability in Cisco Secure Firewall Management Center
Published on September 16, 2026
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.
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.
Vulnerability Analysis
CVE-2026-20295 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.
Weakness Type
What is a Stack Exhaustion Vulnerability?
The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated.
CVE-2026-20295 has been classified to as a Stack Exhaustion vulnerability or weakness.
Products Associated with CVE-2026-20295
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Affected Versions
Cisco Secure Firewall Management Center (FMC):- Version 7.0.0 is affected.
- Version 7.0.0.1 is affected.
- Version 7.0.1 is affected.
- Version 7.0.1.1 is affected.
- Version 7.0.2 is affected.
- Version 7.2.0 is affected.
- Version 7.0.2.1 is affected.
- Version 7.0.3 is affected.
- Version 7.2.0.1 is affected.
- Version 7.0.4 is affected.
- Version 7.2.1 is affected.
- Version 7.0.5 is affected.
- Version 7.3.0 is affected.
- Version 7.2.2 is affected.
- Version 7.3.1 is affected.
- Version 7.2.3 is affected.
- Version 7.2.3.1 is affected.
- Version 7.2.4 is affected.
- Version 7.0.6 is affected.
- Version 7.2.4.1 is affected.
- Version 7.2.5 is affected.
- Version 7.3.1.1 is affected.
- Version 7.4.0 is affected.
- Version 7.0.6.1 is affected.
- Version 7.2.5.1 is affected.
- Version 7.4.1 is affected.
- Version 7.2.6 is affected.
- Version 7.4.1.1 is affected.
- Version 7.0.6.2 is affected.
- Version 7.2.7 is affected.
- Version 7.2.5.2 is affected.
- Version 7.3.1.2 is affected.
- Version 7.2.8 is affected.
- Version 7.6.0 is affected.
- Version 7.4.2 is affected.
- Version 7.2.8.1 is affected.
- Version 7.0.6.3 is affected.
- Version 7.4.2.1 is affected.
- Version 7.2.9 is affected.
- Version 7.0.7 is affected.
- Version 7.7.0 is affected.
- Version 7.4.2.2 is affected.
- Version 7.2.10 is affected.
- Version 7.6.1 is affected.
- Version 7.4.2.3 is affected.
- Version 7.0.8 is affected.
- Version 7.6.2 is affected.
- Version 7.7.10 is affected.
- Version 7.2.10.1 is affected.
- Version 7.0.8.1 is affected.
- Version 7.6.2.1 is affected.
- Version 7.2.10.2 is affected.
- Version 7.7.10.1 is affected.
- Version 7.4.2.4 is affected.
- Version 7.4.3 is affected.
- Version 7.6.3 is affected.
- Version 7.7.11 is affected.
- Version 7.6.4 is affected.
- Version 10.0.0 is affected.
- Version 7.4.4 is affected.
- Version 7.4.5 is affected.
- Version 7.0.9 is affected.
- Version 7.2.11 is affected.
- Version 7.7.12 is affected.
- Version 7.6.5 is affected.
- Version 7.4.6 is affected.
- Version 10.0.1 is affected.
- Version 7.0.0 is affected.
- Version 7.0.0.1 is affected.
- Version 7.0.1 is affected.
- Version 7.0.1.1 is affected.
- Version 7.0.2 is affected.
- Version 7.2.0 is affected.
- Version 7.0.2.1 is affected.
- Version 7.0.3 is affected.
- Version 7.2.0.1 is affected.
- Version 7.0.4 is affected.
- Version 7.2.1 is affected.
- Version 7.0.5 is affected.
- Version 7.3.0 is affected.
- Version 7.2.2 is affected.
- Version 7.2.3 is affected.
- Version 7.3.1 is affected.
- Version 7.2.4 is affected.
- Version 7.0.6 is affected.
- Version 7.2.5 is affected.
- Version 7.2.4.1 is affected.
- Version 7.3.1.1 is affected.
- Version 7.4.0 is affected.
- Version 7.0.6.1 is affected.
- Version 7.2.5.1 is affected.
- Version 7.4.1 is affected.
- Version 7.2.6 is affected.
- Version 7.0.6.2 is affected.
- Version 7.4.1.1 is affected.
- Version 7.2.7 is affected.
- Version 7.2.5.2 is affected.
- Version 7.3.1.2 is affected.
- Version 7.2.8 is affected.
- Version 7.6.0 is affected.
- Version 7.4.2 is affected.
- Version 7.2.8.1 is affected.
- Version 7.0.6.3 is affected.
- Version 7.4.2.1 is affected.
- Version 7.2.9 is affected.
- Version 7.0.7 is affected.
- Version 7.7.0 is affected.
- Version 7.4.2.2 is affected.
- Version 7.2.10 is affected.
- Version 7.6.1 is affected.
- Version 7.4.2.3 is affected.
- Version 7.0.8 is affected.
- Version 7.6.2 is affected.
- Version 7.7.10 is affected.
- Version 7.7.11 is affected.
- Version 7.0.8.1 is affected.
- Version 7.6.2.1 is affected.
- Version 7.7.10.1 is affected.
- Version 7.4.2.4 is affected.
- Version 7.2.10.2 is affected.
- Version 7.4.3 is affected.
- Version 7.6.4 is affected.
- Version 10.0.0 is affected.
- Version 7.4.4 is affected.
- Version 7.0.9 is affected.
- Version 7.2.11 is affected.