CVE-2024-20331

Cisco Adaptive Security Appliance and Firepower Threat Defense Software VPN Authentication DoS Vulnerability

MEDIUM
5.9
CVSS Score
Published: October 23, 2024 at 05:08 PM UTC
Updated: August 11, 2026 at 07:40 PM UTC
3 products affected across 1 vendorAdaptive Security ApplianceSecure Firewall Threat DefenseFirepower Threat Defense

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Severity
MEDIUM5.9
Exploit prediction
EPSS 0.7%
SSVC
No known exploit

Description

A vulnerability in the session 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 prevent users from authenticating. This vulnerability is due to insufficient entropy in the authentication process. An attacker could exploit this vulnerability by determining the handle of an authenticating user and using it to terminate their authentication session. A successful exploit could allow the attacker to force a user to restart the authentication process, preventing a legitimate user from establishing remote access VPN sessions.

Affected

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

9.12.19.12.1.29.12.1.39.12.29.12.2.19.12.2.49.12.2.59.12.2.99.12.39.12.3.129.12.3.29.12.3.79.12.3.99.12.49.12.4.109.12.4.139.12.4.189.12.4.29.12.4.249.12.4.269.12.4.299.12.4.309.12.4.359.12.4.379.12.4.389.12.4.399.12.4.49.12.4.409.12.4.419.12.4.479.12.4.489.12.4.509.12.4.529.12.4.549.12.4.559.12.4.569.12.4.589.12.4.629.12.4.659.12.4.79.12.4.89.14.19.14.1.109.14.1.159.14.1.199.14.1.309.14.1.69.14.29.14.2.139.14.2.159.14.2.49.14.2.89.14.39.14.3.19.14.3.119.14.3.139.14.3.159.14.3.189.14.3.99.14.49.14.4.129.14.4.139.14.4.149.14.4.159.14.4.179.14.4.229.14.4.239.14.4.249.14.4.69.14.4.79.15.19.15.1.19.15.1.109.15.1.159.15.1.169.15.1.179.15.1.219.15.1.79.16.19.16.1.289.16.29.16.2.119.16.2.139.16.2.149.16.2.39.16.2.79.16.39.16.3.149.16.3.159.16.3.199.16.3.239.16.3.39.16.49.16.4.149.16.4.189.16.4.199.16.4.279.16.4.389.16.4.399.16.4.429.16.4.489.16.4.99.17.19.17.1.109.17.1.119.17.1.139.17.1.159.17.1.209.17.1.309.17.1.339.17.1.79.17.1.99.18.19.18.1.39.18.29.18.2.59.18.2.79.18.2.89.18.39.18.3.399.18.3.469.18.3.539.18.3.559.18.3.569.18.49.18.4.59.18.4.89.19.19.19.1.129.19.1.189.19.1.229.19.1.249.19.1.279.19.1.59.19.1.99.20.19.20.1.59.20.29.8.19.8.1.59.8.1.79.8.29.8.2.149.8.2.159.8.2.179.8.2.209.8.2.249.8.2.269.8.2.289.8.2.339.8.2.359.8.2.389.8.2.459.8.2.89.8.39.8.3.119.8.3.149.8.3.169.8.3.189.8.3.219.8.3.269.8.3.299.8.3.89.8.49.8.4.109.8.4.129.8.4.159.8.4.179.8.4.209.8.4.229.8.4.259.8.4.269.8.4.299.8.4.39.8.4.329.8.4.339.8.4.349.8.4.359.8.4.399.8.4.409.8.4.419.8.4.439.8.4.449.8.4.459.8.4.469.8.4.489.8.4.79.8.4.8

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-330CWE-331

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