CVE-2026-20290NVD

Vulnerability Summary

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.

Severity Level

MEDIUM(5.8)

Published Date

Sep 16, 2026

Last Modified

Sep 17, 2026

Exploitation Status

No confirmed exploitation yet

EPSS Score (30-Day)

0.19%Probability

Root Weakness (CWE)

CWE-805: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v3.1 Base Metrics — Score 5.8 (MEDIUM)

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeChanged

ConfidentialityNone

IntegrityNone

AvailabilityLow

Affected & Patched Versions

Affected Versions

Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.0
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.0.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.1.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.0
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.2.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.3
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.0.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.4
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.5
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.3.0
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.3
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.3.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.4
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.6
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.5
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.4.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.3.1.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.4.0
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.6.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.5.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.4.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.6
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.6.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.4.1.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.7
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.5.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.3.1.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.8
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.6.0
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.4.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.8.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.6.3
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.4.2.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.9
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.7
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.4.2.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.10
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.6.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.4.2.3
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.8
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.6.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.8.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.6.2.1
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.4.2.4
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.10.2
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.4.3
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.6.4
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.4.4
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.0.9
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.2.11
Cisco Cisco Secure Firewall Threat Defense (FTD) Software >= 7.4.7

Patched Versions

Not provided by cveorg for this CVE.

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