CVE-2024-20494
Status: AnalyzedHigh (8.6)—
A vulnerability in the TLS cryptography functionality of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition.
This vulnerability is due to improper data validation during the TLS 1.3 handshake. An attacker could exploit this vulnerability by sending a crafted TLS 1.3 packet to an affected system through a TLS 1.3-enabled listening socket. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
Read full descriptionShow less
Note: This vulnerability can also impact the integrity of a device by causing VPN HostScan communication failures or file transfer failures when Cisco ASA Software is upgraded using Cisco Adaptive Security Device Manager (ASDM).
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
- Base score: 8.6
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.51%
- Percentile among all scored CVEs: 42
- Score date: 10/6/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
🎯 ATT&CK techniques
How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.
- Exploitation
T1190Exploit Public-Facing Applicationinitial access92 % - Primary impact
T1499Endpoint Denial of Serviceimpact95 % - Secondary impact
T1565.002Transmitted Data Manipulationimpact60 %
AV:N/AC:L/PR:N permite explotación remota sin autenticación (T1190). La vulnerabilidad causa recarga del dispositivo (DoS, T1499). La falla en validación TLS puede afectar integridad de comunicaciones (CWE-1287, T1565.002 secundario).
Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.
🛡️ ATT&CK mitigations that cover these techniques
Affected technologies (2)
CWEs
- CWE-1287
References
Raw JSON (NVD)
Show
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