CVE-2026-20039 — Heap Inspection in Cisco Secure Firewall Adaptive Security Appliance Software

CWE-244 — Heap Inspection4 documents4 sources
Severity
8.6HIGHNVD
EPSS
0.2%
top 60.62%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
2
Cisco Secure Firewall Adaptive Security Appliance SoftwareCisco Secure Firewall Threat Defense Software
Timeline
PublishedMar 4

Description

A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to ineffective memory management of the VPN web server. An attacker could exploit this vulnerability by sending a large number of crafted HTTP requests to an affected device. A successful exploit…

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:HExploitability: 3.9 | Impact: 4.0

Affected Packages2 packages

🔴Vulnerability Details

2
GHSA
GHSA-ch3j-whf9-3xp2: A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FT↗2026-03-04
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CVEList
Cisco Adaptive Security Appliance and Firepower Threat Defense Software SSL VPN Authentication Denial of Service Vulnerability↗2026-03-04
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📋Vendor Advisories

1
Cisco
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software VPN Web Server Denial of Service Vulnerability↗2026-03-04
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CVE-2026-20039 — Heap Inspection in Cisco | cvebase