CVE-2020-3564
Low
No strong exploitation signal.
CVSS base
5.3
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS — probability of exploitation (30 days)
1.3%
69.8th percentile
CISA KEV
Not listed
Weakness / dates
CWE-436
Published 2020-10-21 · modified 2026-08-11
CVSS breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
| Attack Vector | N | Network |
| Attack Complexity | L | Low |
| Privileges Required | N | None |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | N | None |
| Integrity | L | Low |
| Availability | N | None |
Timeline
- 2020-10-21 — Published (NVD)
- 2026-08-11 — Last modified (NVD)
Description
A vulnerability in the FTP inspection engine of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass FTP inspection. The vulnerability is due to ineffective flow tracking of FTP traffic. An attacker could exploit this vulnerability by sending crafted FTP traffic through an affected device. A successful exploit could allow the attacker to bypass FTP inspection and successfully complete FTP connections.