CVE-2026-20006 (GCVE-0-2026-20006)

Vulnerability from cvelistv5 – Published: 2026-03-04 17:37 – Updated: 2026-03-04 20:51
VLAI
Title
Cisco Firepower Threat Defense Software and Cisco FirePOWER Services TLS with Snort 3 Denial of Service Vulnerability
Summary
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.
Severity
5.8 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
Impacted products
Vendor Product Version
Cisco Cisco Secure Firewall Threat Defense (FTD) Software Affected: 7.2.0
Affected: 7.2.0.1
Affected: 7.2.1
Affected: 7.3.0
Affected: 7.2.2
Affected: 7.2.3
Affected: 7.3.1
Affected: 7.2.4
Affected: 7.2.5
Affected: 7.2.4.1
Affected: 7.3.1.1
Affected: 7.4.0
Affected: 7.2.5.1
Affected: 7.4.1
Affected: 7.2.6
Affected: 7.4.1.1
Affected: 7.2.7
Affected: 7.2.5.2
Affected: 7.3.1.2
Affected: 7.2.8
Affected: 7.6.0
Affected: 7.4.2
Affected: 7.2.8.1
Affected: 7.4.2.1
Affected: 7.2.9
Affected: 7.4.2.2
Affected: 7.2.10
Affected: 7.6.1
Affected: 7.4.2.3
Affected: 7.6.2
Affected: 7.6.2.1
Affected: 7.4.2.4
Affected: 7.2.10.2
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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