CVE-2018-15388

Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software WebVPN Denial of Service Vulnerability

HIGH

8.6

CVSS Score

Published: May 3, 2019 at 02:30 PM UTC

Updated: August 11, 2026 at 07:37 PM UTC

14 products affected across 1 vendorAdaptive Security ApplianceSecure Firewall Threat DefenseASA 5580

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Severity

HIGH8.6

Exploit prediction

EPSS 2%

SSVC

No known 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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Adaptive Security Appliance · Cisco

95%

v < 9.4.4.34v < 9.6.4.25v < 9.8.4v < 9.9.2.509.5 ≤ v < 9.6.4.259.7 ≤ v < 9.8.49.9 ≤ v < 9.9.2.50

Affected range stops below 9.4.4.34, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.6.4.25, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.8.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.9.2.50, so it looks safe — our inference, not a vendor statement

cisco-asa-5505 (environment) · cisco-asa-5510 (environment) · cisco-asa-5512-x (environment) · cisco-asa-5515-x (environment) · cisco-asa-5520 (environment) · cisco-asa-5525-x (environment) · cisco-asa-5540 (environment) · cisco-asa-5545-x (environment) · cisco-asa-5550 (environment) · cisco-asa-5555-x (environment) · cisco-asa-5580 (environment) · cisco-asa-5585-x (environment)

Secure Firewall Threat Defense · Cisco

95%

v < 6.2.3.12

ASA 5505 · Ciscodevice

80%

All versions

ASA 5510 · Ciscodevice

80%

All versions

Asa 5512-X · Ciscodevice

80%

All versions