CVE WatchAug 11, 2026

CVE-2024-20481

Cisco ASA and FTD Denial-of-Service Vulnerability

CVSS

5.8

Medium

EPSS

15.9%

p97

KEV

YES

Oct 24, 2024

Exploit Today

0-100

Published: Oct 23, 2024 · Last modified: Aug 11, 2026 · CWE-772

EPSS · 30d

15.9%EPSS · 30 days15.9%

2026-08-022026-08-31

KEV catalog record

Product

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

Vulnerability

Cisco ASA and FTD Denial-of-Service Vulnerability

Added to KEV

Oct 24, 2024

Remediate by

Nov 14, 2024

Known ransomware use

Summary description

Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) contain a missing release of resource after effective lifetime vulnerability that could allow an unauthenticated, remote attacker to cause a denial-of-service (DoS) of the RAVPN service.

Required action

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Notes

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-bf-dos-vDZhLqrW ; https://nvd.nist.gov/vuln/detail/CVE-2024-20481

Technical description

A vulnerability in the Remote Access VPN (RAVPN) service of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) of the RAVPN service. This vulnerability is due to resource exhaustion. An attacker could exploit this vulnerability by sending a large number of VPN authentication requests to an affected device. A successful exploit could allow the attacker to exhaust resources, resulting in a DoS of the RAVPN service on the affected device. Depending on the impact of the attack, a reload of the device may be required to restore the RAVPN service. Services that are not related to VPN are not affected. Cisco Talos discussed these attacks in the blog post Large-scale brute-force activity targeting VPNs, SSH services with commonly used login credentials.

Official references

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