Cisco · Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD)
CVE-2020-3259
Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Information Disclosure Vulnerability
What it is
A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to retrieve memory contents on an affected device, which could lead to the disclosure of confidential information. The vulnerability is due to a buffer tracking issue when the software parses invalid URLs that are requested from the web services interface. An attacker could exploit this vulnerability by sending a crafted GET request to the web services interface. A successful exploit could allow the attacker to retrieve memory contents, which could lead to the disclosure of confidential information. Note: This vulnerability affects only specific AnyConnect and WebVPN configurations. For more information, see the Vulnerable Products section.
CISA: Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) contain an information disclosure vulnerability. An attacker could retrieve memory contents on an affected device, which could lead to the disclosure of confidential information due to a buffer tracking issue when the software parses invalid URLs that are requested from the web services interface. This vulnerability affects only specific AnyConnect and WebVPN configurations.
What to do
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Deadline for US federal agencies: March 7, 2024
More exploited flaws from Cisco
| Added | Vulnerability | Product | Severity | Attack chance |
|---|---|---|---|---|
| Oct 24, 2024 | ASA and FTD Denial-of-Service | Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) | Medium 5.8 | 16% |
| Apr 24, 2024 | ASA and FTD Denial of Service | Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) | High 8.6 | 70% |
| Apr 24, 2024 | ASA and FTD Privilege Escalation | Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) | Medium 6.0 | 19% |
| Nov 3, 2021 | ASA and FTD Read-Only Path Traversal | Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) | High 7.5 | >99.9% |
| Nov 3, 2021 | ASA and FTD Cross-Site Scripting (XSS) | Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) | Medium 6.1 | 86% |
| Oct 14, 2026 | Relative Path Traversal | Secure Email Gateway | Critical 9.8 | 2.2% |
| Sep 30, 2026 | Hex Encoding | Catalyst SD-WAN Manager | Critical 9.8 | 39% |
| Sep 16, 2026 | Incorrect Use of Privileged APIs | Identity Services Engine | Critical 10.0 | 76% |
Sources: Known Exploited Vulnerabilities (CISA, public domain), CVE records (cve.org) and EPSS (FIRST). The chance of attacks is the EPSS estimate that someone will try to exploit the flaw in the next 30 days.