CVE-2019-1703: Cisco Firepower Threat Defense Software Packet Processing Denial of Service Vulnerability

Severity: high (CVSS 8.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-05-03 · updated 2026-08-11
Weakness: CWE-400

Description

A vulnerability in the internal packet-processing functionality of Cisco Firepower Threat Defense (FTD) Software for the Cisco Firepower 2100 Series could allow an unauthenticated, remote attacker to cause an affected device to stop processing traffic, resulting in a denial of service (DoS) condition. The vulnerability is due to a logic error, which may prevent ingress buffers from being replenished under specific traffic conditions. An attacker could exploit this vulnerability by sending a series of crafted packets to an affected device. A successful exploit could allow the attacker to consume all input buffers, which are shared between all interfaces, leading to a queue wedge condition in all active interfaces. This situation would cause an affected device to stop processing any incoming traffic and result in a DoS condition until the device is reloaded manually.

Affected products

Cisco Firepower Threat Defense Software: from 6.2.1 before 6.2.3.12 — fixed in 6.2.3.12

How to fix

Upgrade to a fixed version: Cisco Firepower Threat Defense Software 6.2.3.12. Check the vendor advisory for mitigations.

References

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