CVE-2023-20031
CVE-2023-20031 is a medium-severity vulnerability in Cisco Firepower Threat Defense with a CVSS 3.x base score of 4.0. 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-244.
Key facts
- Severity: Medium (CVSS 3.x base score 4.0)
- EPSS exploit prediction: 0% (20th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-244
- Affected product: Cisco Firepower Threat Defense
- Published:
- Last modified:
Description
A vulnerability in the SSL/TLS certificate handling of Snort 3 Detection Engine integration with Cisco Firepower 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 that occurs when an SSL/TLS certificate that is under load is accessed when it is initiating an SSL connection. Under specific, time-based constraints, an attacker could exploit this vulnerability by sending a high rate of SSL/TLS connection requests to be inspected by the Snort 3 detection engine on an affected device. A successful exploit could allow the attacker to cause the Snort 3 detection engine to reload, resulting in either a bypass or a denial of service (DoS) condition, depending on device configuration. The Snort detection engine will restart automatically. No manual intervention is required.
Frequently asked questions
- What is CVE-2023-20031?
- A vulnerability in the SSL/TLS certificate handling of Snort 3 Detection Engine integration with Cisco Firepower 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 that occurs when an SSL/TLS certificate that is under load is accessed when it is initiating an SSL connection. Under specific, time-based constraints, an attacker could exploit this vulnerability by sending a high rate of SSL/TLS connection requests to be inspected by the Snort 3 detection engine on an affected device. A successful exploit could allow the attacker to cause the Snort 3 detection engine to reload, resulting in either a bypass or a denial of service (DoS) condition, depending on device configuration. The Snort detection engine will restart automatically. No manual intervention is required.
- How severe is CVE-2023-20031?
- CVE-2023-20031 has a CVSS 3.x base score of 4.0, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
- Is CVE-2023-20031 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-20031?
- CVE-2023-20031 primarily affects Cisco Firepower Threat Defense. In total, 15 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2023-20031?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2023-20031 published?
- CVE-2023-20031 was published on 2023-11-01 and last updated on 2026-06-17.
References
Affected products (15)
- cpe:2.3:a:cisco:firepower_threat_defense:6.7.0:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:6.7.0.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:6.7.0.2:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:6.7.0.3:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.0.0:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.0.0.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.0.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.0.1.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.0.2:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.0.2.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.0.3:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.0.4:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.0.5:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.2.0:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.2.0.1:*:*:*:*:*:*:*
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