Description
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 products
cisco: secure firewall threat defense
References1
- sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAd… Vendor AdvisoryMitigation
Metrics
- CVSS 3.1
-
5.8
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L - EPSS — exploit probability
- 0% percentile: 38 · as of 12 November 2026
- CWE
- CWE-388
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