CVE-2020-3452Actively exploitedAdded to KEV 2021-11-03

Cisco ASA and FTD Read-Only Path Traversal Vulnerability

Cisco, Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD)

Description

Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) contain an improper input validation vulnerability when HTTP requests process URLs. An attacker could exploit this vulnerability by sending a crafted HTTP request containing directory traversal character sequences to an affected device. A successful exploit could allow the attacker to view arbitrary files within the web services file system on the targeted device.

CVSS severity for this advisory hasn't been enriched from NVD yet, check back shortly.

EPSS, exploit probability

Critical

100.0%

estimated chance of real-world exploitation in the next 30 days, higher than 100.0% of every CVE FIRST.org scores

Refreshed 10/28/2026, via FIRST.org's EPSS model, not CVSS, this measures likelihood of exploitation, not how severe it would be.

Required action

Apply updates per vendor instructions.

CISA-recommended due date: 2022-05-03

CWE-20

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