Cisco Adaptive Security Appliance Software
CVE-2019-1687
A vulnerability in the TCP proxy functionality for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to restart unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to an error in TCP-based packet inspection, which could cause the TCP packet to have an invalid Layer 2 (L2)-formatted header. An attacker could exploit this vulnerability by sending a crafted TCP packet sequence to the targeted device. A successful exploit could allow the attacker to cause a DoS condition.
What this means for your business
- It affects Cisco Adaptive Security Appliance Software. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 3% chance of attack attempts being seen in the next 30 days, ranking above 86% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Cisco Adaptive Security Appliance Software, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Not sure if your company is exposed?
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Scoring
- CVSS
- 7.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Weakness
- CWE-20
- Assigned by
- psirt@cisco.com
Dates
- Published
- 2019-05-03
- Last modified
- 2026-08-11
- Sources
- NVD
Affected products
- Cisco Adaptive Security Appliance Software- 9.4.4.34, 9.5 - 9.6.4.25, 9.7 - 9.8.4, 9.9 - 9.9.2.50, 9.10 - 9.10.1.17
- Cisco Asa 5505all versions
- Cisco Asa 5510all versions
- Cisco Asa 5512-Xall versions
- Cisco Asa 5515-Xall versions
- Cisco Asa 5520all versions
- Cisco Asa 5525-Xall versions
- Cisco Asa 5540all versions
- Cisco Asa 5545-Xall versions
- Cisco Asa 5550all versions
- Cisco Asa 5555-Xall versions
- Cisco Asa 5580all versions
As listed in the NVD configuration data. Not a statement about your estate.