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Severe, 6 weeks1496Projects326

1496 severe, 6 weeks · 326 projects

CiscoCVE-2026-20323

Cisco Secure Firewall: improper certificate validation

Cisco

CVE-2026-20323 · Published Sep 16, 2026 · updated Sep 18, 2026

High8.3
No fix yet
Cisco advisory

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.

Affected versions

PackageAffectedFixed in
Cisco Secure Firewall Management Center (FMC)
Product
<= 7.0.0No fix yet
<= 7.0.0.1No fix yet
<= 7.0.1No fix yet
<= 7.0.1.1No fix yet
Cisco Secure Firewall Threat Defense (FTD) Software
Product
<= 7.0.0No fix yet
<= 7.0.0.1No fix yet
<= 7.0.1No fix yet
<= 7.0.1.1No fix yet
Details and references

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