VDB-137701 · CVE-2019-1873 · BID 109123

Cisco ASA/Firepower Threat Defense Cryptographic Driver SSL Packet resource consumption

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.

A vulnerability classified as problematic was found in Cisco ASA and Firepower Threat Defense (Firewall Software) (the affected version is unknown). Affected by this vulnerability is an unknown code of the component Cryptographic Driver. The manipulation as part of a SSL Packet leads to a resource consumption vulnerability. The CWE definition for the vulnerability is CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. As an impact it is known to affect availability. The summary by CVE is:

A vulnerability in the cryptographic driver for Cisco Adaptive Security Appliance Software (ASA) and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reboot unexpectedly. The vulnerability is due to incomplete input validation of a Secure Sockets Layer (SSL) or Transport Layer Security (TLS) ingress packet header. An attacker could exploit this vulnerability by sending a crafted TLS/SSL packet to an interface on the targeted device. An exploit could allow the attacker to cause the device to reload, which will result in a denial of service (DoS) condition. Note: Only traffic directed to the affected system can be used to exploit this vulnerability. This vulnerability affects systems configured in routed and transparent firewall mode and in single or multiple context mode. This vulnerability can be triggered by IPv4 and IPv6 traffic. A valid SSL or TLS session is required to exploit this vulnerability.

The weakness was released 07/10/2019 as cisco-sa-20190710-asa-ftd-dos as confirmed advisory (Website). The advisory is shared at tools.cisco.com. This vulnerability is known as CVE-2019-1873 since 12/06/2018. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading eliminates this vulnerability.

Entries connected to this vulnerability are available at VDB-213288, VDB-213292, VDB-213293 and VDB-213303.






CPE 2.3info

CPE 2.2info


VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍


VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 7.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CNA Base Score: 8.6
CNA Vector (Cisco Systems, Inc.): 🔍



VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍


Class: Resource consumption
CWE: CWE-400 / CWE-404

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍


12/06/2018 🔍
07/10/2019 +216 days 🔍
07/11/2019 +1 days 🔍
10/24/2023 +1566 days 🔍


Vendor: cisco.com

Advisory: cisco-sa-20190710-asa-ftd-dos
Status: Confirmed

CVE: CVE-2019-1873 (🔍)
SecurityFocus: 109123

See also: 🔍


Created: 07/11/2019 12:41 PM
Updated: 10/24/2023 02:13 PM
Changes: 07/11/2019 12:41 PM (40), 07/03/2020 07:01 PM (18), 10/24/2023 02:10 PM (4), 10/24/2023 02:13 PM (12)
Complete: 🔍
Cache ID: 44:A3D:40


No comments yet. Languages: en.

Please log in to comment.

Want to stay up to date on a daily basis?

Enable the mail alert feature now!