CVE-2019-1694

Cisco Adaptive Security Appliance Software and Cisco Firepower Threat Defense Software TCP Timer Handling Denial of Service Vulnerability

HIGH

8.6

CVSS Score

Published: May 3, 2019 at 03:10 PM UTC

Updated: August 11, 2026 at 07:37 PM UTC

15 products affected across 1 vendorAdaptive Security ApplianceSecure Firewall Threat DefenseASA 5580

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Severity

HIGH8.6

Exploit prediction

EPSS 3%

SSVC

No known exploit

Description

A vulnerability in the TCP processing engine of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to the improper handling of TCP traffic. An attacker could exploit this vulnerability by sending a specific sequence of packets at a high rate through an affected device. A successful exploit could allow the attacker to temporarily disrupt traffic through the device while it reboots.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Adaptive Security Appliance · Cisco

95%

v < 9.10.1.17v < 9.4.4.34v < 9.6.4.25v < 9.8.4v < 9.9.2.509.10 ≤ v < 9.10.1.179.5 ≤ v < 9.6.4.259.7 ≤ v < 9.8.49.9 ≤ v < 9.9.2.50

Affected range stops below 9.10.1.17, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.4.4.34, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.6.4.25, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.8.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.9.2.50, so it looks safe — our inference, not a vendor statement

cisco-asa-5505 (environment) · cisco-asa-5510 (environment) · cisco-asa-5512-x (environment) · cisco-asa-5515-x (environment) · cisco-asa-5520 (environment) · cisco-asa-5525-x (environment) · cisco-asa-5540 (environment) · cisco-asa-5545-x (environment) · cisco-asa-5550 (environment) · cisco-asa-5555-x (environment) · cisco-asa-5580 (environment) · cisco-asa-5585-x (environment)

Secure Firewall Threat Defense · Cisco

95%

v < 6.2.3.126.3.0 ≤ v < 6.3.0.3

Firepower Threat Defense · Cisco

60%

v < 6.3.0.3

Affected range stops below 6.2.3.12, so it looks safe — our inference, not a vendor statement

Affected range stops below 6.3.0.3, so it looks safe — our inference, not a vendor statement

ASA 5505 · Ciscodevice

80%

All versions

ASA 5510 · Ciscodevice