Secure Firewall ASA and FTD

CVE-2024-20493: A vulnerability in the login authentication functionality of the Remote Access SSL VPN feature of Cisco Ada…

A vulnerability in the login authentication functionality of the Remote Access SSL VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to deny further VPN user authentications for several minutes, resulting in a temporary denial of service (DoS) condition.

Published

ExploitedNot in CISA KEV
Ransomware useNot reportedPer CISA
SeverityMEDIUMCVSS 3.1 5.3
EPSS0.55%Chance of exploitation in 30 days
Public exploitNot tracked
FixNot yet

Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.

Affected and fixed versions

Product / branchFixed in
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.8See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.12See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.14See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.15See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.15See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.15See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.15See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.15See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.15See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.15See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.15See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.16See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.17See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.17See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.17See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.17See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.17See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.17See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.17See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.17See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.17See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.17See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.17See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.18See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.19See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.19See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.19See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.19See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.19See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.19See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.19See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.19See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.19See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.19See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.20See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.20See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.20See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.20See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.20See the advisory
Cisco Adaptive Security Appliance (ASA) Software 9.20See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.2See the advisory
Cisco Firepower Threat Defense Software 6.6See the advisory
Cisco Firepower Threat Defense Software 6.6See the advisory
Cisco Firepower Threat Defense Software 6.6See the advisory
Cisco Firepower Threat Defense Software 6.6See the advisory
Cisco Firepower Threat Defense Software 6.6See the advisory
Cisco Firepower Threat Defense Software 6.6See the advisory
Cisco Firepower Threat Defense Software 6.6See the advisory
Cisco Firepower Threat Defense Software 6.6See the advisory
Cisco Firepower Threat Defense Software 6.6See the advisory
Cisco Firepower Threat Defense Software 6.6See the advisory
Cisco Firepower Threat Defense Software 6.6See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.4See the advisory
Cisco Firepower Threat Defense Software 6.7See the advisory
Cisco Firepower Threat Defense Software 6.7See the advisory
Cisco Firepower Threat Defense Software 6.7See the advisory
Cisco Firepower Threat Defense Software 6.7See the advisory
Cisco Firepower Threat Defense Software 7.0See the advisory
Cisco Firepower Threat Defense Software 7.0See the advisory
Cisco Firepower Threat Defense Software 7.0See the advisory
Cisco Firepower Threat Defense Software 7.0See the advisory
Cisco Firepower Threat Defense Software 7.0See the advisory
Cisco Firepower Threat Defense Software 7.0See the advisory
Cisco Firepower Threat Defense Software 7.0See the advisory
Cisco Firepower Threat Defense Software 7.0See the advisory
Cisco Firepower Threat Defense Software 7.0See the advisory
Cisco Firepower Threat Defense Software 7.0See the advisory
Cisco Firepower Threat Defense Software 7.0See the advisory
Cisco Firepower Threat Defense Software 7.0See the advisory
Cisco Firepower Threat Defense Software 7.1See the advisory
Cisco Firepower Threat Defense Software 7.1See the advisory
Cisco Firepower Threat Defense Software 7.1See the advisory
Cisco Firepower Threat Defense Software 7.1See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.2See the advisory
Cisco Firepower Threat Defense Software 7.3See the advisory
Cisco Firepower Threat Defense Software 7.3See the advisory
Cisco Firepower Threat Defense Software 7.3See the advisory
Cisco Firepower Threat Defense Software 7.3See the advisory
Cisco Firepower Threat Defense Software 7.4See the advisory
Cisco Firepower Threat Defense Software 7.4See the advisory
Cisco Firepower Threat Defense Software 7.4See the advisory
Cisco Firepower Threat Defense Software 7.4See the advisory

Always confirm against the vendor advisory, which lists every fixed hotfix.

What it is

A vulnerability in the login authentication functionality of the Remote Access SSL VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to deny further VPN user authentications for several minutes, resulting in a temporary denial of service (DoS) condition. This vulnerability is due to ineffective handling of memory resources during the authentication process. An attacker could exploit this vulnerability by sending crafted packets, which could cause resource exhaustion of the authentication process. A successful exploit could allow the attacker to deny authentication for Remote Access SSL VPN users for several minutes, resulting in a temporary DoS condition.

Exploitation

The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.

Sources

KEV status, EPSS score and vendor data refreshed automatically, last on 11 Oct 2026.

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