CVE-2023-20177
CVE-2023-20177
In short
A flaw in Cisco Firepower Threat Defense's SSL inspection feature can cause the detection engine to crash and restart when processing certain SSL/TLS connections with URL filtering enabled. An attacker can trigger this crash remotely, potentially bypassing security checks or disrupting threat detection.
Technical detail
This vulnerability exploits a logic error in Snort 3 detection engine when inspecting SSL/TLS connections configured with URL Categories on SSL file policies or access control policies with TLS server identity discovery. An unauthenticated remote attacker can send crafted SSL/TLS traffic to trigger an unexpected engine restart, resulting in either detection bypass or temporary DoS; automatic recovery occurs without manual intervention.
Summary generated and translated by AI from the official description.
A vulnerability in the SSL file policy implementation of Cisco Firepower Threat Defense (FTD) Software that occurs when the SSL/TLS connection is configured with a URL Category and the Snort 3 detection engine could allow an unauthenticated, remote attacker to cause the Snort 3 detection engine to unexpectedly restart. This vulnerability exists because a logic error occurs when a Snort 3 detection engine inspects an SSL/TLS connection that has either a URL Category configured on the SSL file policy or a URL Category configured on an access control policy with TLS server identity discovery enabled. Under specific, time-based constraints, an attacker could exploit this vulnerability by sending a crafted SSL/TLS connection through an affected device. A successful exploit could allow the attacker to trigger an unexpected reload of the Snort 3 detection engine, resulting in either a bypass or denial of service (DoS) condition, depending on device configuration. The Snort 3 detection engine will restart automatically. No manual intervention is required.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:L