8.6High

Cisco Secure Firewall Threat Defense

CVE-2018-0230

A vulnerability in the internal packet-processing functionality of Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series Security Appliances 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 the affected software improperly validating IP Version 4 (IPv4) and IP Version 6 (IPv6) packets after the software reassembles the packets (following IP Fragmentation). An attacker could exploit this vulnerability by sending a series of malicious, fragmented IPv4 or IPv6 packets to an affected device. A successful exploit could allow the attacker to cause Snort processes on the affected device to hang at 100% CPU utilization, which could cause the device to stop processing traffic and result in a DoS condition until the device is reloaded manually. This vulnerability affects Cisco Firepower Threat Defense (FTD) Software Releases 6.2.1 and 6.2.2, if the software is running on a Cisco Firepower 2100 Series Security Appliance. Cisco Bug IDs: CSCvf91098.

What this means for your business

  • It affects Cisco Secure Firewall Threat Defense. 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 2% chance of attack attempts being seen in the next 30 days, ranking above 83% of all known flaws.

What to do

  1. 1Check whether your company or your suppliers run Cisco Secure Firewall Threat Defense, and which version. The affected versions are listed further down this page.
  2. 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
8.6 (v3.0)
Vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Weakness
CWE-400
Assigned by
psirt@cisco.com

Dates

Published
2018-04-19
Last modified
2026-08-11
Sources
NVD

Affected products

  • Cisco Secure Firewall Threat Defense6.2.1, 6.2.2
  • Cisco Adaptive Security Appliance Software9.8\(2\)

As listed in the NVD configuration data. Not a statement about your estate.

References