CVE•Published 2023-11-01•Modified 2026-08-11•0 articles on news•5 live references•NVD data

CVE-2023-20177Cisco · Secure_firewall_threat_defense

Vulnerability data via NVD (ingested)

CVSS v3.1
4.0
MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:L
EPSS percentile
42
Exploit Prediction Scoring System · top 58% of all CVEs
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.

Timeline
Published 2023-11-01
Modified 2026-08-11

External references

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More intel sources (5)

Known PoCs on GitHub (1)

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