Cisco FTD CLI DoS via Improper Input Validation
CVE-2026-20064 Published on March 4, 2026
A vulnerability in of Cisco Secure Firewall Threat Defense (FTD) Software could allow an authenticated, local attacker to cause the device to unexpectedly reload, causing a denial of service (DoS) condition. This vulnerability is due to improper validation of user-supplied input. An attacker with a low-privileged account could exploit this vulnerability by using crafted commands at the CLI prompt. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
Vulnerability Analysis
CVE-2026-20064 is exploitable with local system access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.
Weakness Type
NULL Pointer Dereference
A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. NULL pointer dereference issues can occur through a number of flaws, including race conditions, and simple programming omissions.
Affected Versions
Cisco Secure Firewall Threat Defense (FTD) Software:- Version 6.4.0 is affected.
- Version 6.4.0.1 is affected.
- Version 6.4.0.3 is affected.
- Version 6.4.0.2 is affected.
- Version 6.4.0.4 is affected.
- Version 6.4.0.5 is affected.
- Version 6.4.0.6 is affected.
- Version 6.4.0.7 is affected.
- Version 6.4.0.8 is affected.
- Version 6.4.0.9 is affected.
- Version 6.4.0.10 is affected.
- Version 6.4.0.11 is affected.
- Version 6.4.0.12 is affected.
- Version 6.4.0.13 is affected.
- Version 6.4.0.14 is affected.
- Version 6.4.0.15 is affected.
- Version 6.4.0.16 is affected.
- Version 6.4.0.17 is affected.
- Version 6.4.0.18 is affected.
- Version 7.0.0 is affected.
- Version 7.0.0.1 is affected.
- Version 7.0.1 is affected.
- Version 7.0.1.1 is affected.
- Version 7.0.2 is affected.
- Version 7.0.2.1 is affected.
- Version 7.0.3 is affected.
- Version 7.0.4 is affected.
- Version 7.0.5 is affected.
- Version 7.0.6 is affected.
- Version 7.0.6.1 is affected.
- Version 7.0.6.2 is affected.
- Version 7.0.6.3 is affected.
- Version 7.0.7 is affected.
- Version 7.0.8 is affected.
- Version 7.0.8.1 is affected.
- Version 7.1.0 is affected.
- Version 7.1.0.1 is affected.
- Version 7.1.0.2 is affected.
- Version 7.1.0.3 is affected.
- Version 7.2.0 is affected.
- Version 7.2.0.1 is affected.
- Version 7.2.1 is affected.
- Version 7.2.2 is affected.
- Version 7.2.3 is affected.
- Version 7.2.4 is affected.
- Version 7.2.4.1 is affected.
- Version 7.2.5 is affected.
- Version 7.2.5.1 is affected.
- Version 7.2.6 is affected.
- Version 7.2.7 is affected.
- Version 7.2.5.2 is affected.
- Version 7.2.8 is affected.
- Version 7.2.8.1 is affected.
- Version 7.2.9 is affected.
- Version 7.2.10 is affected.
- Version 7.2.10.2 is affected.
- Version 7.3.0 is affected.
- Version 7.3.1 is affected.
- Version 7.3.1.1 is affected.
- Version 7.3.1.2 is affected.
- Version 7.4.0 is affected.
- Version 7.4.1 is affected.
- Version 7.4.1.1 is affected.
- Version 7.4.2 is affected.
- Version 7.4.2.1 is affected.
- Version 7.4.2.2 is affected.
- Version 7.4.2.3 is affected.
- Version 7.4.2.4 is affected.
- Version 7.6.0 is affected.
- Version 7.6.1 is affected.
- Version 7.6.2 is affected.
- Version 7.6.2.1 is affected.
- Version 7.7.0 is affected.
- Version 7.7.10 is affected.
- Version 7.7.10.1 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.