Cisco Secure Firewall Threat Defense Software Snort 2 SSL/TLS Denial of Service Vulnerability
cve-program · CVE-2026-20290
PublishedA vulnerability in SSL/TLS certificate parsing in the Snort 2 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the Snort 2 Detection Engine to restart. This vulnerability is due to incomplete validation of the SSL certificate. An attacker could exploit this vulnerability by sending a crafted SSL connection setup request to be parsed by Snort 2. A successful exploit could allow the attacker to cause the Snort 2 Detection Engine to restart unexpectedly, resulting in a denial of service (DoS) condition.
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cve-program · CVE-2026-20290
PublishedCisco Secure Firewall Threat Defense Software Snort 2 SSL/TLS Denial of Service Vulnerability
A vulnerability in SSL/TLS certificate parsing in the Snort 2 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the Snort 2 Detection Engine to restart. This vulnerability is due to incomplete validation of the SSL certificate. An attacker could exploit this vulnerability by sending a crafted SSL connection setup request to be parsed by Snort 2. A successful exploit could allow the attacker to cause the Snort 2 Detection Engine to restart unexpectedly, resulting in a denial of service (DoS) condition.
- Source published
- 16 Sep 2026 20:19:02 UTC
- Source modified
- 17 Sep 2026 17:29:41 UTC
- Saved here
- 23 Oct 2026 15:48:27 UTC
- Source terms
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CVSS 3.1 · 5.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L