Cisco Adaptive Security Appliance and Firepower Threat Defense Software SSL VPN Authentication Denial of Service Vulnerability (Cisco Cisco Secure Firewall Adaptive Security Appliance (ASA) Software)

CVE-2026-20039
HIGH 8.6

At a glance

Source
NVD
EPSS
EPSS 0.37 % · percentile 31 ()
State
PUBLISHED
Published
Updated
Assigner
cisco
NVD status
Analyzed

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 could allow the attacker to cause the device to reload, resulting in a DoS condition.

Weaknesses (CWE)

  • CWE-244 — Improper Clearing of Heap Memory Before Release

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 8.6CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hcisco
CVSS 3.1HIGH 8.6CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:HNVD · psirt@cisco.com (Secondary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Cisco · Cisco Secure Firewall Adaptive Security Appliance (ASA) Softwareaffected 9.12.3 ; affected 9.12.1 ; affected 9.12.2 ; affected 9.12.4 ; affected 9.12.3.2 ; affected 9.12.3.7
Cisco · Cisco Secure Firewall Threat Defense (FTD) Softwareaffected 6.4.0.1 ; affected 6.4.0.2 ; affected 6.4.0.5 ; affected 6.4.0 ; affected 6.4.0.3 ; affected 6.4.0.4

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD