CVE-2026-20100 — Classic Buffer Overflow in Cisco Secure Firewall Adaptive Security Appliance Software

CWE-120 — Classic Buffer OverflowCWE-330 — Use of Insufficiently Random ValuesCWE-401 — Missing Release of Memory after Effective LifetimeCWE-770 — Allocation of Resources Without Limits or Throttling4 documents4 sources
Severity
7.7HIGHNVD
EPSS
0.2%
top 55.93%
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
Latest updateMar 5

Description

A vulnerability in the LUA interperter of the Remote Access SSL VPN feature of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Threat Defense (FTD) Software could allow an authenticated, remote attacker with a valid VPN connection to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This does not affect the management or MUS interfaces. This vulnerability is due to trusting user input without validation in the LUA inte…

CVSS vector

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

Affected Packages2 packages

🔴Vulnerability Details

2
CVEList
CVE-2026-20100: A vulnerability in the LUA interperter of the Remote Access SSL VPN feature of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Se↗2026-03-04
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GHSA
GHSA-chrm-52hv-4ff4: A vulnerability in the LUA interperter of the Remote Access SSL VPN feature of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Se↗2026-03-04
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📋Vendor Advisories

1
Cisco
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Denial of Service Vulnerabilities↗2026-03-05
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CVE-2026-20100 — Classic Buffer Overflow in Cisco | cvebase