Cisco Secure Firewall Threat Defense Software Snort 3 Memory Management Denial of Service Vulnerability
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · Low
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
Summary
A vulnerability in the memory management handling for 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 restart. This vulnerability is due to a logic error in memory management when a device is performing Snort 3 SSL packet inspection. An attacker could exploit this vulnerability by sending crafted SSL packets through an established connection to be parsed by the Snort 3 Detection Engine. A successful exploit could allow the attacker to cause a denial of service (DoS) condition when the Snort 3 Detection Engine unexpectedly restarts.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Cisco | Cisco Secure Firewall Threat Defense (FTD) Software | 7.4.0; 7.4.1; 7.4.1.1; 7.6.0; 7.4.2; 7.4.2.1 | — | No fix listed | CNA |
- Cisco Secure Firewall Threat Defense (FTD) Software VendorCisco Affected 7.4.0; 7.4.1; 7.4.1.1; 7.6.0; 7.4.2; 7.4.2.1 Fixed in — No fix listed CNA
CPE configurations NVD · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:cisco:secure_firewall_threat_defense:7.4.0:*:*:*:*:*:*:* | 7.4.0 | Vulnerable | Cisco |
| cpe:2.3:a:cisco:secure_firewall_threat_defense:7.4.1:*:*:*:*:*:*:* | 7.4.1 | Vulnerable | Cisco |
| cpe:2.3:a:cisco:secure_firewall_threat_defense:7.4.1.1:*:*:*:*:*:*:* | 7.4.1.1 | Vulnerable | Cisco |
| cpe:2.3:a:cisco:secure_firewall_threat_defense:7.4.2:*:*:*:*:*:*:* | 7.4.2 | Vulnerable | Cisco |
| cpe:2.3:a:cisco:secure_firewall_threat_defense:7.4.2.1:*:*:*:*:*:*:* | 7.4.2.1 | Vulnerable | Cisco |
| cpe:2.3:a:cisco:secure_firewall_threat_defense:7.6.0:*:*:*:*:*:*:* | 7.6.0 | Vulnerable | Cisco |
- cpe:2.3:a:cisco:secure_firewall_threat_defense:7.4.0:*:*:*:*:*:*:* Versions 7.4.0 Vulnerable ·Cisco
- cpe:2.3:a:cisco:secure_firewall_threat_defense:7.4.1:*:*:*:*:*:*:* Versions 7.4.1 Vulnerable ·Cisco
- cpe:2.3:a:cisco:secure_firewall_threat_defense:7.4.1.1:*:*:*:*:*:*:* Versions 7.4.1.1 Vulnerable ·Cisco
- cpe:2.3:a:cisco:secure_firewall_threat_defense:7.4.2:*:*:*:*:*:*:* Versions 7.4.2 Vulnerable ·Cisco
- cpe:2.3:a:cisco:secure_firewall_threat_defense:7.4.2.1:*:*:*:*:*:*:* Versions 7.4.2.1 Vulnerable ·Cisco
- cpe:2.3:a:cisco:secure_firewall_threat_defense:7.6.0:*:*:*:*:*:*:* Versions 7.6.0 Vulnerable ·Cisco
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-20052
- 2026-10-03 Alias added: GHSA-f3x2-jxv4-r583
References
Advisory 1
More Cisco Secure Firewall Threat Defense vulnerabilities
- TI-2025-14628 Buffer overflow in Cisco Secure Firewall Adaptive Security Appliance Software KEVCVSS 3.1CRITICAL 9.9
- TI-2021-19919 Apache Log4j2 JNDI features do not protect against attacker controlled LDAP and other JNDI related endpoints KEVCVSS 3.1CRITICAL 10.0
- TI-2023-06973 Authentication bypass in Cisco Adaptive Security Appliance Software KEVCVSS 3.1CRITICAL 9.1
- TI-2026-82192 Denial of service in Cisco Secure Firewall ASA and FTD SSL VPN KEVCVSS 3.1HIGH 8.6
- TI-2026-16533 Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense… KEVCVSS 3.1HIGH 8.6
- TI-2025-14657 Missing authorization in Cisco Secure Firewall Adaptive Security Appliance Software KEVCVSS 3.1HIGH 8.6
Sources
- CVE-2026-20052 · CVE Program
- CVE-2026-20052 · NVD
- FIRST EPSS
- GHSA-f3x2-jxv4-r583 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences