PT-2026-23009 · Cisco+1 · Cisco Secure Firewall Threat Defense (Ftd)+1

Published 2026-03-04 · Updated 2026-03-04 · CVE-2026-20006

Positive Technologies (AI Summary)

CVSS v3.1

5.8

Medium

Base vector

AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L

Name of the Vulnerable Software and Affected Versions Cisco Secure Firewall Threat Defense (FTD) Software (affected versions not specified)

Description A flaw exists in the TLS cryptography functionality within the Snort 3 Detection Engine. This issue could allow a remote attacker to trigger an unexpected restart of the Snort 3 Detection Engine, leading to a denial of service (DoS) condition. The root cause is an improper implementation of the TLS protocol. An attacker can exploit this by sending a specially crafted TLS packet to a vulnerable system. TLS 1.3 is not affected.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

DoS

Weakness Enumeration

CWE-388

Related Identifiers

CVE-2026-20006

Affected Products

Cisco Secure Firewall Threat Defense (Ftd)

Snort 3 Detection Engine

References · 4

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tcp-dos-rHfqnwRg · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-20006 · Security Note
• https://twitter.com/CVEnew/status/2029272797747335454 · Twitter Post
• https://t.me/CVEtracker/46345 · Telegram Post