7.4High

Cisco Adaptive Security Appliance Software

CVE-2020-3334

A vulnerability in the ARP packet processing of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series Security Appliances could allow an unauthenticated, adjacent attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition on an affected device. The vulnerability is due to incorrect processing of ARP packets received by the management interface of an affected device. An attacker could exploit this vulnerability by sending a series of unicast ARP packets in a short timeframe that would reach the management interface of an affected device. A successful exploit could allow the attacker to consume resources on an affected device, which would prevent the device from sending internal system keepalives and eventually cause the device to reload, resulting in a denial of service (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 from inside the same network, without a login, and without anyone at your company clicking anything.
  • FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 36% of all known flaws.

What to do

  1. 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.
  2. 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Scoring

CVSS
7.4 (v3.1)
Vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Weakness
CWE-399
Assigned by
psirt@cisco.com

Dates

Published
2020-05-06
Last modified
2026-08-11
Sources
NVD

Affected products

  • Cisco Adaptive Security Appliance Software9.10 - 9.10.1.37, 9.12 - 9.12.3, 9.13 - 9.13.1.2
  • Cisco Secure Firewall Threat Defense- 6.6.0
  • Cisco Firepower 2110all versions
  • Cisco Firepower 2120all versions
  • Cisco Firepower 2130all versions
  • Cisco Firepower 2140all versions

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

References