SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2018-15388

A vulnerability in the WebVPN login process of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause increased CPU utilization on an affected device.

HIGH 8.6EPSS 1.98%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.98%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A vulnerability in the WebVPN login process of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause increased CPU utilization on an affected device. The vulnerability is due to excessive processing load for existing WebVPN login operations. An attacker could exploit this vulnerability by sending multiple WebVPN login requests to the device. A successful exploit could allow the attacker to increase CPU load on the device, resulting in a denial of service (DoS) condition.

CVSS 3.0
8.6 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS
1.98% probability · 80th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-400
Affected
cisco/adaptive security appliance software · cisco/secure firewall threat defense
Source
psirt@cisco.com
EPSS trend
0%3%5%27 October 2026: 1.98%27 October 202627 October 2026

EPSS 2.0% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.