Incorrect numeric conversion in Cisco Adaptive Security Appliance Software
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
Summary
A vulnerability in the hardware-based SSL/TLS cryptography functionality of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series Appliances could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to an implementation error within the cryptographic functions for SSL/TLS traffic processing when they are offloaded to the hardware. An attacker could exploit this vulnerability by sending a crafted stream of SSL/TLS traffic to an affected device. A successful exploit could allow the attacker to cause an unexpected error in the hardware-based cryptography engine, which could cause the device to reload.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Cisco | Cisco Adaptive Security Appliance (ASA) Software | 9.16.4; 9.18.2; 9.18.2.5 | — | No fix listed | CNA |
| Cisco | Cisco Firepower Threat Defense Software | 7.2.1; 7.2.2; 7.2.3 | — | No fix listed | CNA |
- Cisco Adaptive Security Appliance (ASA) Software VendorCisco Affected 9.16.4; 9.18.2; 9.18.2.5 Fixed in — No fix listed CNA
- Cisco Firepower Threat Defense Software VendorCisco Affected 7.2.1; 7.2.2; 7.2.3 Fixed in — No fix listed CNA
CPE configurations NVD · 10
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:cisco:secure_firewall_threat_defense:7.2.1:*:*:*:*:*:*:* | 7.2.1 | Vulnerable | Cisco |
| cpe:2.3:a:cisco:secure_firewall_threat_defense:7.2.2:*:*:*:*:*:*:* | 7.2.2 | Vulnerable | Cisco |
| cpe:2.3:a:cisco:secure_firewall_threat_defense:7.2.3:*:*:*:*:*:*:* | 7.2.3 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:adaptive_security_appliance_software:9.16.4:*:*:*:*:*:*:* | 9.16.4 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.2:*:*:*:*:*:*:* | 9.18.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.2.5:*:*:*:*:*:*:* | 9.18.2.5 | Vulnerable | Cisco |
| cpe:2.3:h:cisco:firepower_2110:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:firepower_2120:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:firepower_2130:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:firepower_2140:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
- cpe:2.3:a:cisco:secure_firewall_threat_defense:7.2.1:*:*:*:*:*:*:* Versions 7.2.1 Vulnerable ·Cisco
- cpe:2.3:a:cisco:secure_firewall_threat_defense:7.2.2:*:*:*:*:*:*:* Versions 7.2.2 Vulnerable ·Cisco
- cpe:2.3:a:cisco:secure_firewall_threat_defense:7.2.3:*:*:*:*:*:*:* Versions 7.2.3 Vulnerable ·Cisco
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.16.4:*:*:*:*:*:*:* Versions 9.16.4 Vulnerable ·Cisco
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.2:*:*:*:*:*:*:* Versions 9.18.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.2.5:*:*:*:*:*:*:* Versions 9.18.2.5 Vulnerable ·Cisco
- cpe:2.3:h:cisco:firepower_2110:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:firepower_2120:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:firepower_2130:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:firepower_2140:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2023-20006
- 2026-10-03 Alias added: GHSA-hvf9-xw27-729c
References
Advisory 1
More Cisco Adaptive Security Appliance Software vulnerabilities
- TI-2025-14628 Buffer overflow in Cisco Secure Firewall Adaptive Security Appliance Software KEVCVSS 3.1CRITICAL 9.9
- TI-2016-05454 Buffer overflow in Cisco Adaptive Security Appliance (ASA) Software through 9.4.2.3 on… KEVCVSS 3.1HIGH 8.8
- 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-2023-20006 · CVE Program
- CVE-2023-20006 · NVD
- FIRST EPSS
- GHSA-hvf9-xw27-729c · 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