CVE-2026-20006: medium-severity vulnerability in Cisco Secure Firewall Threat Defense (FTD)…
Cisco Firepower Threat Defense Software and Cisco FirePOWER Services TLS with Snort 3 Denial of Service Vulnerability
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.8epss 0.4%
A vulnerability in the TLS cryptography functionality of the Snort 3 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to unexpectedly restart, resulting in a denial of service (DoS) condition.
This vulnerability is due to improper implementation of the TLS protocol. An attacker could exploit this vulnerability by sending a crafted TLS packet to an affected system. A successful exploit could allow the attacker to cause a device that is running Cisco Secure FTD Software to drop network traffic, resulting in a DoS condition.
Note: TLS 1.3 is not affected by this vulnerability.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
Affected products
Cisco · Cisco Secure Firewall Threat Defense (FTD) SoftwareRelated CVEs — Cisco Secure Firewall Threat Defense (FTD)…
In the same product, most dangerous first.
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