CVE-2026-20006
published 2026-03-04CVE-2026-20006: A vulnerability in the TLS cryptography functionality of the Snort 3 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could allow an…
PriorityP434medium5.8CVSS 3.1
AVNACLPRNUINSCCNINAL
EPSS
0.37%
29.9th percentile
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.
Affected
34 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
| cisco | cisco_secure_firewall_threat_defense_software | — | — |
CVSS provenance
nvdv3.15.8MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
vendor_cisco5.8MEDIUM
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Cisco
Cisco Secure Firewall Threat Defense Software TLS with Snort 3 Detection Engine Denial of Service Vulnerability
vendor_cisco·2026-03-04·CVSS 5.8
CVE-2026-20006 [MEDIUM] CWE-388 Cisco Secure Firewall Threat Defense Software TLS with Snort 3 Detection Engine Denial of Service Vulnerability
Cisco Secure Firewall Threat Defense Software TLS with Snort 3 Detection Engine Denial of Service Vulnerability
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 vulnerabili
Cisco
Cisco Secure Firewall Threat Defense Software TLS with Snort 3 Detection Engine Denial of Service Vulnerability
vendor_cisco·CVSS 3.1
CVE-2026-20006 Cisco Secure Firewall Threat Defense Software TLS with Snort 3 Detection Engine Denial of Service Vulnerability
CVE-2026-20006: Cisco Secure Firewall Threat Defense Software TLS with Snort 3 Detection Engine Denial of Service Vulnerability
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 th
GHSA
GHSA-mh5f-h37q-2qm8: A vulnerability in the TLS cryptography functionality of the Snort 3 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could all
ghsa_unreviewed·2026-03-04
CVE-2026-20006 [MEDIUM] GHSA-mh5f-h37q-2qm8: A vulnerability in the TLS cryptography functionality of the Snort 3 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could all
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.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-03-04
Published