CVE-2023-20006
CVE-2023-20006 is a high-severity vulnerability in Cisco Firepower Threat Defense with a CVSS 3.x base score of 8.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-681.
Key facts
- Severity: High (CVSS 3.x base score 8.6)
- EPSS exploit prediction: 1% (56th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-681
- Affected product: Cisco Firepower Threat Defense
- Published:
- Last modified:
Description
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.
Frequently asked questions
- What is CVE-2023-20006?
- 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.
- How severe is CVE-2023-20006?
- CVE-2023-20006 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2023-20006 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-20006?
- CVE-2023-20006 primarily affects Cisco Firepower Threat Defense. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2023-20006?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2023-20006 published?
- CVE-2023-20006 was published on 2023-06-28 and last updated on 2026-06-17.
References
Affected products (6)
- cpe:2.3:a:cisco:firepower_threat_defense:7.2.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.2.2:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.2.3:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.16.4:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.2.5:*:*:*:*:*:*:*
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