CVE-2020-3259

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.

At a glance

Exploitability

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

In the wild

CISA lists this as exploited in real attacks. Treat as urgent.

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. 2024-02-15 Exploited in the wildAdded to CISA's Known Exploited Vulnerabilities list
4. 2024-03-07 Remediation deadlineCISA's due date for federal agencies to fix it
5. 2026-08-12 05:17 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: yes, CISA lists it. This puts it above everything that is not.
• Exploit odds: 71.5% in the next 30 days (EPSS).
• Severity: 7.5 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2020-05-06 17:15 UTC

Last modified

2026-08-12 05:17 UTC

Added to CISA KEV

2024-02-15

Exploit probability

71.5% · EPSS, next 30 days

Weakness

CWE-200 · Information exposure

Record status

Analyzed

Affected

• Cisco Secure Firewall Threat Defense < 6.2.3.16
• Cisco Secure Firewall Threat Defense < 6.3.0.6
• Cisco Secure Firewall Threat Defense < 6.4.0.9
• Cisco Secure Firewall Threat Defense < 6.5.0.5
• Cisco Adaptive Security Appliance Software < 9.8.4.20
• Cisco Adaptive Security Appliance Software < 9.9.2.67
• Cisco Adaptive Security Appliance Software < 9.10.1.40
• Cisco Adaptive Security Appliance Software < 9.12.3.9

Attack profile CVSS 3.1 · 7.5

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

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-2020-3259.md and follow it. Check whether this project is affected by CVE-2020-3259. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

Copy as ticket · More options · Status badge