Security Resilience

CVE-2024-20494

Cisco Adaptive Security Appliance Software 9.19.1 … 9.20.3

Published
23 October 2024
Modified
11 August 2026
Patch / advisory
View advisory
CVSS Score v3.1 8.6
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS Score 0.0052 43th percentile
Risk Priority 62 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2024-20494 is a high-severity Improper Validation of Specified Type of Input (CWE-1287) vulnerability in Cisco Adaptive Security Appliance Software. Its CVSS base score is 8.6 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Junk Data (T1001.001); ranked at the 43th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

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…

more

(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. 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).

CWE(s)
CWE-1287

Related Threats

MITRE ATT&CK Enterprise Techniques

T1001.001 Junk Data Command And Control
Adversaries may add junk data to protocols used for command and control to make detection more difficult.
attack.mitre.org →
T1003.001 LSASS Memory Credential Access
Adversaries may attempt to access credential material stored in the process memory of the Local Security Authority Subsystem Service (LSASS).
attack.mitre.org →
T1003.003 NTDS Credential Access
Adversaries may attempt to access or create a copy of the Active Directory domain database in order to steal credential information, as well as obtain other information about domain members such as devices, users, and access rights.
attack.mitre.org →
T1003.005 Cached Domain Credentials Credential Access
Adversaries may attempt to access cached domain credentials used to allow authentication to occur in the event a domain controller is unavailable.
attack.mitre.org →
T1003.008 /etc/passwd and /etc/shadow Credential Access
Adversaries may attempt to dump the contents of <code>/etc/passwd</code> and <code>/etc/shadow</code> to enable offline password cracking.
attack.mitre.org →
T1007 System Service Discovery Discovery
Adversaries may try to gather information about registered local system services.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-20408Same product: Cisco Adaptive Security Appliance Software
CVE-2024-20341Same product: Cisco Adaptive Security Appliance Software
CVE-2024-20481Same product: Cisco Adaptive Security Appliance Software
CVE-2023-20095Same product: Cisco Adaptive Security Appliance Software
CVE-2024-20493Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20008Same product: Cisco Adaptive Security Appliance Software
CVE-2024-20358Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20022Same product: Cisco Adaptive Security Appliance Software
CVE-2024-20299Same product: Cisco Adaptive Security Appliance Software
CVE-2024-20297Same product: Cisco Adaptive Security Appliance Software

Affected Assets

cisco
adaptive security appliance software
9.19.1, 9.19.1.12, 9.19.1.18, 9.19.1.22, 9.19.1.24
cisco
secure firewall threat defense
7.3.0, 7.3.1, 7.3.1.1, 7.3.1.2, 7.4.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.1.1
  • V1.4.2
  • V2.1.1
  • V2.2.2

Mitigating Controls (NIST 800-53 r5) AI

SI-10 Information Input Validation good match

SI-10 directly requires validation of information inputs, which structurally prevents type-validation failures from being introduced or exploitable.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 partial match
blocks

Secure SDLC practices directly require proper input type validation during development.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.5.14 Information transfer partial match
removes
A.5.15 Access control partial match
removes
A.5.16 Identity management partial match
removes
A.5.17 Authentication information partial match
removes
A.5.18 Access rights partial match
removes
A.8.10 Information deletion partial match
removes

References