SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2024-20481

Cisco ASA and FTD Denial-of-Service Vulnerability

KEVMEDIUM 5.8EPSS 15.8%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 14 November 2024). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

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.

CVSS 3.1
5.8 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
EPSS
15.75% probability · 97th percentile
CISA KEV
Listed 24 October 2024 · due 14 November 2024
Weakness
CWE-772
Affected
cisco/secure firewall threat defense · cisco/adaptive security appliance software
Source
psirt@cisco.com

CISA notes

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-bf-dos-vDZhLqrW ; https://nvd.nist.gov/vuln/detail/CVE-2024-20481

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.