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
0.40%
32.6th 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
67 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
VulDB
Cisco Secure Firewall Threat Defense Software up to 7.6.2.1 TLS Protocol 7pk error (cisco-sa-ftd-tcp-dos-rHfqnwRg)
vuldb·2026-08-22·CVSS 5.8
CVE-2026-20006 [MEDIUM] Cisco Secure Firewall Threat Defense Software up to 7.6.2.1 TLS Protocol 7pk error (cisco-sa-ftd-tcp-dos-rHfqnwRg)
A vulnerability has been found in Cisco Secure Firewall Threat Defense Software and classified as problematic. Affected by this vulnerability is an unknown functionality of the component TLS Protocol Handler. This manipulation causes 7pk error.
The identification of this vulnerability is CVE-2026-20006. It is possible to initiate the attack remotely. There is no exploit available.
The affected component should be upgraded.
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