🔐 CVE Alert

CVE-2026-20323

HIGH 8.3

Cisco Secure Firewall Management Center and Secure Firewall Threat Defense Software sftunnel Unauthorized Authentication Bypass Vulnerability

CVSS Score
8.3
EPSS Score
0.0%
EPSS Percentile
0th

A vulnerability in the sftunnel inter-device communication protocol of Cisco Secure FMC Software and Cisco Secure FTD Software could allow an unauthenticated, adjacent attacker to impersonate the peer device and obtain access at the level of the manager role, which is equivalent to root. This vulnerability is due to improper management of the TLS certificate for the sftunnel management connection. An attacker could exploit this vulnerability by connecting to the sftunnel port using a crafted TLS certificate. A successful exploit could allow the attacker to become a registered sftunnel peer with root access. Note: The attack is successful only if the sftunnel connection is down or the attack can disrupt the sftunnel connection long enough to execute the attack.

CWE CWE-295
Vendor cisco
Product cisco secure firewall management center (fmc)
Ecosystems
Industries
NetworkingTelecommunications
Published Sep 16, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Attack Vector
Adjacent
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

Affected Versions

Cisco / Cisco Secure Firewall Management Center (FMC)
7.0.0 7.0.0.1 7.0.1 7.0.1.1 7.0.2 7.2.0 7.0.2.1 7.0.3 7.2.0.1 7.0.4 7.2.1 7.0.5 7.3.0 7.2.2 7.3.1 7.2.3 7.2.3.1 7.2.4 7.0.6 7.2.4.1 7.2.5 7.3.1.1 7.4.0 7.0.6.1 7.2.5.1 7.4.1 7.2.6 7.4.1.1 7.0.6.2 7.2.7 7.2.5.2 7.3.1.2 7.2.8 7.6.0 7.4.2 7.2.8.1 7.0.6.3 7.4.2.1 7.2.9 7.0.7 7.7.0 7.4.2.2 7.2.10 7.6.1 7.4.2.3 7.0.8 7.6.2 7.7.10 7.2.10.1 7.0.8.1 7.6.2.1 7.2.10.2 7.7.10.1 7.4.2.4 7.4.3 7.6.3 7.7.11 7.6.4 10.0.0 7.4.4 7.4.5 7.0.9 7.2.11 7.7.12 7.6.5 7.4.6 10.0.1 7.4.7 7.0.10
Cisco / Cisco Secure Firewall Threat Defense (FTD) Software
7.0.0 7.0.0.1 7.0.1 7.0.1.1 7.0.2 7.2.0 7.0.2.1 7.0.3 7.2.0.1 7.0.4 7.2.1 7.0.5 7.3.0 7.2.2 7.2.3 7.3.1 7.2.4 7.0.6 7.2.5 7.2.4.1 7.3.1.1 7.4.0 7.0.6.1 7.2.5.1 7.4.1 7.2.6 7.0.6.2 7.4.1.1 7.2.7 7.2.5.2 7.3.1.2 7.2.8 7.6.0 7.4.2 7.2.8.1 7.0.6.3 7.4.2.1 7.2.9 7.0.7 7.7.0 7.4.2.2 7.2.10 7.6.1 7.4.2.3 7.0.8 7.6.2 7.7.10 7.7.11 7.0.8.1 7.6.2.1 7.7.10.1 7.4.2.4 7.2.10.2 7.4.3 7.6.4 10.0.0 7.4.4 7.0.9 7.2.11 7.4.7 7.0.10

References

NVD ↗ CVE.org ↗ EPSS Data ↗
sec.cloudapps.cisco.com: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmcftd-sftun-multivulns-WGVHOrN3