CVE-2020-3187

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 conduct directory traversal attacks and obtain read and delete access to sensitive files on a targeted system. The vulnerability is due to a lack of proper input validation of the HTTP URL. An attacker could exploit this vulnerability by sending a crafted HTTP request containing directory traversal character sequences. An exploit could allow the attacker to view or delete arbitrary files on the targeted system. When the device is reloaded after exploitation of this vulnerability, any files that were deleted are restored. The attacker can only view and delete files within the web services file system. This file system is enabled when the affected device is configured with either WebVPN or AnyConnect features. This vulnerability can not be used to obtain access to ASA or FTD system files or underlying operating system (OS) files. Reloading the affected device will restore all files within the web services file system.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of data exposure, data tampering.

Exploit odds

96.5% chance of exploitation in the next 30 days (EPSS). Higher than most.

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2019-12-12 00:00 UTC ReservedThe CVE id was reserved by its CNA
2. 2020-05-06 17:15 UTC PublishedDisclosed publicly on CVE.org and NVD
3. 2026-08-11 19:33 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 96.5% in the next 30 days (EPSS).
• Severity: 9.1 CRITICAL (CVSS).
• Fix: a patch or advisory is linked.
• It meets the bar for Drop everything: critical, and exploited or very likely to be.

Details

Published

2020-05-06 17:15 UTC

Last modified

2026-08-11 19:33 UTC

Exploit probability

96.5% · EPSS, next 30 days

Weakness

CWE-22 · Path traversal

Record status

Modified

Affected

• Cisco Secure Firewall Threat Defense < 6.2.3.16
• Cisco Secure Firewall Threat Defense < 6.3.0.6
• Cisco Secure Firewall Threat Defense < 6.4.0.8
• Cisco Secure Firewall Threat Defense < 6.5.0.4
• Cisco Asa 5505 Firmware 9.6\(4\)
• Cisco Asa 5510 Firmware 9.6\(4\)
• Cisco Asa 5512-x Firmware 9.6\(4\)
• Cisco Asa 5515-x Firmware 9.6\(4\)

Attack profile CVSS 3.1 · 9.1

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2020-3187.md and follow it. Check whether this project is affected by CVE-2020-3187. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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