CVE-2019-1978: Cisco Firepower Threat Defense Software Stream Reassembly Bypass Vulnerability

Severity: medium (CVSS 5.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 9.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2019-11-05 · updated 2026-08-11
Weakness: CWE-264

Description

A vulnerability in the stream reassembly component of Cisco Firepower Threat Defense Software, Cisco FirePOWER Services Software for ASA, and Cisco Firepower Management Center Software could allow an unauthenticated, remote attacker to bypass filtering protections. The vulnerability is due to improper reassembly of traffic streams. An attacker could exploit this vulnerability by sending crafted streams through an affected device. An exploit could allow the attacker to bypass filtering and deliver malicious requests to protected systems that would otherwise be blocked.

Affected products

Cisco Firepower Services Software For Asa: all versions
Cisco Firepower Management Center: from 2.9.12 through 2.9.12.15; from 2.9.13 through 2.9.13.6; from 2.9.14.0 through 2.9.14.5; 2.9.15, 2.9.16
Cisco Firepower Threat Defense Software: all versions

References

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