CVE-2023-20070

CVE-2023-20070 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

Description

A vulnerability in the TLS 1.3 implementation of the Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the Snort 3 detection engine to unexpectedly restart. This vulnerability is due to a logic error in how memory allocations are handled during a TLS 1.3 session. Under specific, time-based constraints, an attacker could exploit this vulnerability by sending a crafted TLS 1.3 message sequence through an affected device. A successful exploit could allow the attacker to cause the Snort 3 detection engine to reload, resulting in a denial of service (DoS) condition. While the Snort detection engine reloads, packets going through the FTD device that are sent to the Snort detection engine will be dropped. The Snort detection engine will restart automatically. No manual intervention is required.

Frequently asked questions

What is CVE-2023-20070?
A vulnerability in the TLS 1.3 implementation of the Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the Snort 3 detection engine to unexpectedly restart. This vulnerability is due to a logic error in how memory allocations are handled during a TLS 1.3 session. Under specific, time-based constraints, an attacker could exploit this vulnerability by sending a crafted TLS 1.3 message sequence through an affected device. A successful exploit could allow the attacker to cause the Snort 3 detection engine to reload, resulting in a denial of service (DoS) condition. While the Snort detection engine reloads, packets going through the FTD device that are sent to the Snort detection engine will be dropped. The Snort detection engine will restart automatically. No manual intervention is required.
How severe is CVE-2023-20070?
CVE-2023-20070 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 none, and availability low.
Is CVE-2023-20070 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-20070?
CVE-2023-20070 primarily affects Cisco Firepower Threat Defense. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-20070?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-20070 published?
CVE-2023-20070 was published on 2023-11-01 and last updated on 2026-06-17.

References

Affected products (2)

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