CVE-2019-1970: Cisco Firepower Threat Defense Software File Policy Bypass Vulnerability

Severity: high (CVSS 7.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-08-08 · updated 2026-08-11
Weakness: CWE-693

Description

A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) protocol inspection engine of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass the configured file policies on an affected system. The vulnerability is due to errors when handling specific SSL/TLS messages. An attacker could exploit this vulnerability by sending crafted HTTP packets that would flow through an affected system. A successful exploit could allow the attacker to bypass the configured file policies and deliver a malicious payload to the protected network.

Affected products

Cisco Firepower Management Center: 6.3.0, 6.4.0
Cisco Firepower Threat Defense Software: before 6.4.1 — fixed in 6.4.1

How to fix

Upgrade to a fixed version: Cisco Firepower Threat Defense Software 6.4.1. Check the vendor advisory for mitigations.

References

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