CVE-2024-20481

Exp

A vulnerability in the Remote Access VPN (RAVPN) service of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) of the RAVPN service. This vulnerability is due to resource exhaustion. An attacker could exploit this vulnerability by sending a large number of VPN authentication requests to an affected device. A successful exploit could allow the attacker to exhaust resources, resulting in a DoS of the RAVPN service on the affected device. Depending on the impact of the attack, a reload of the device may be required to restore the RAVPN service. Services that are not related to VPN are not affected. Cisco Talos discussed these attacks in the blog post Large-scale brute-force activity targeting VPNs, SSH services with commonly used login credentials.

Published: 2024-10-23 Last update: 2025-10-28 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2024-20481 is rated Active Exploitation (79.3/100): CVSS Medium severity, with high exploitation likelihood (EPSS 11.12%, 93th percentile). CISA KEV confirms active exploitation (added 2024-10-24) affecting Cisco / Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD). a weakness (CWE-772) Unauthenticated remote administrative access may be possible. The CISA remediation deadline has passed—treat as an emergency patch priority.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

CISA KEV Record for CVE-2024-20481

Name: Cisco ASA and FTD Denial-of-Service Vulnerability · CISA KEV detail

Exploit added: 2024-10-24

Action due: 2024-11-14

Required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Exploit prediction scoring system (EPSS) score for CVE-2024-20481

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-12-14 12.67% 11.12% -1.55%
2 2025-12-01 3.25% 12.67% +9.42%
3 2025-11-21 — 3.25% —

Full EPSS history (23 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-20481

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 3.9 1.4 [email protected]
5.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 3.9 1.4 [email protected]

Weakness enumeration for CVE-2024-20481

Affected software / configurations for CVE-2024-20481

Vendor Product Version Raw CPE
cisco firepower_threat_defense_software 6.2.3 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.1 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.2 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.2:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.3 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.3:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.4 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.4:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.5 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.5:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.6 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.6:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.7 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.7:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.8 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.8:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.9 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.9:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.10 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.10:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.11 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.11:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.12 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.12:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.13 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.13:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.14 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.14:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.15 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.15:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.16 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.16:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.17 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.17:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.2.3.18 cpe:2.3:a:cisco:firepower_threat_defense_software:6.2.3.18:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.1 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.2 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.2:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.3 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.3:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.4 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.4:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.5 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.5:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.6 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.6:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.7 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.7:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.8 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.8:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.9 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.9:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.10 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.10:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.11 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.11:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.12 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.12:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.13 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.13:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.14 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.14:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.15 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.15:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.16 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.16:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.17 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.17:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.4.0.18 cpe:2.3:a:cisco:firepower_threat_defense_software:6.4.0.18:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.6.0 cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.0:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.6.0.1 cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.0.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.6.1 cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.6.3 cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.3:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.6.4 cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.4:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.6.5 cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.5:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.6.5.1 cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.5.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.6.5.2 cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.5.2:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.6.7 cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.7:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.6.7.1 cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.7.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.6.7.2 cpe:2.3:a:cisco:firepower_threat_defense_software:6.6.7.2:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.7.0 cpe:2.3:a:cisco:firepower_threat_defense_software:6.7.0:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.7.0.1 cpe:2.3:a:cisco:firepower_threat_defense_software:6.7.0.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.7.0.2 cpe:2.3:a:cisco:firepower_threat_defense_software:6.7.0.2:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 6.7.0.3 cpe:2.3:a:cisco:firepower_threat_defense_software:6.7.0.3:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.0.0 cpe:2.3:a:cisco:firepower_threat_defense_software:7.0.0:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.0.0.1 cpe:2.3:a:cisco:firepower_threat_defense_software:7.0.0.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.0.1 cpe:2.3:a:cisco:firepower_threat_defense_software:7.0.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.0.1.1 cpe:2.3:a:cisco:firepower_threat_defense_software:7.0.1.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.0.2 cpe:2.3:a:cisco:firepower_threat_defense_software:7.0.2:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.0.2.1 cpe:2.3:a:cisco:firepower_threat_defense_software:7.0.2.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.0.3 cpe:2.3:a:cisco:firepower_threat_defense_software:7.0.3:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.0.4 cpe:2.3:a:cisco:firepower_threat_defense_software:7.0.4:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.0.5 cpe:2.3:a:cisco:firepower_threat_defense_software:7.0.5:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.0.6 cpe:2.3:a:cisco:firepower_threat_defense_software:7.0.6:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.0.6.1 cpe:2.3:a:cisco:firepower_threat_defense_software:7.0.6.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.0.6.2 cpe:2.3:a:cisco:firepower_threat_defense_software:7.0.6.2:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.1.0 cpe:2.3:a:cisco:firepower_threat_defense_software:7.1.0:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.1.0.1 cpe:2.3:a:cisco:firepower_threat_defense_software:7.1.0.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.1.0.2 cpe:2.3:a:cisco:firepower_threat_defense_software:7.1.0.2:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.1.0.3 cpe:2.3:a:cisco:firepower_threat_defense_software:7.1.0.3:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.2.0 cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.0:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.2.0.1 cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.0.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.2.1 cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.2.2 cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.2:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.2.3 cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.3:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.2.4 cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.4:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.2.4.1 cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.4.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.2.5 cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.5:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.2.5.1 cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.5.1:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.2.5.2 cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.5.2:*:*:*:*:*:*:*
cisco firepower_threat_defense_software 7.2.6 cpe:2.3:a:cisco:firepower_threat_defense_software:7.2.6:*:*:*:*:*:*:*

References for CVE-2024-20481

cvelogic Threat Intelligence