Cyber Resilience

CVE-2024-20359

Cisco Adaptive Security Appliance Software 9.12.1 … 9.8.4.8

CISA KEVActive ExploitationEUVD ExploitedPublic PoC
Published
24 April 2024
Modified
11 August 2026
KEV Added
24 April 2024
Patch / advisory
CVSS Score v3.1 6.0
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.19 97th percentile
Risk Priority 75 floored blend · peak EPSS

Summary

CVE-2024-20359 is a medium-severity Code Injection (CWE-94) vulnerability in Cisco Adaptive Security Appliance Software. Its CVSS base score is 6.0 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 3% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

A vulnerability in a legacy capability for preloading VPN clients and plug-ins affects Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software. The issue stems from improper validation of files read from system flash memory and could permit an authenticated local attacker to execute arbitrary code with root-level privileges after a device reload. Administrator privileges are required, and the injected code can persist across reboots, prompting Cisco to raise the Security Impact Rating from Medium to High. The flaw carries a CVSS 3.1 score of 6.0 and is associated with CWE-94.

An attacker with local administrative access can exploit the vulnerability by placing a crafted file on the disk0: file system of an affected device. Successful exploitation allows arbitrary code execution on the next reload, enabling alteration of system behavior that survives reboots.

Cisco has published a security advisory detailing the issue, and the vulnerability appears in CISA's Known Exploited Vulnerabilities catalog. The associated EPSS score rose materially from a low baseline to a peak of 0.0118 on 2024-04-25 before receding, indicating post-disclosure exploitation interest.

A Talos Intelligence report links the vulnerability to the ArcaneDoor espionage campaign targeting perimeter network devices.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A vulnerability in a legacy capability that allowed for the preloading of VPN clients and plug-ins and that has been available in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, local…

more

attacker to execute arbitrary code with root-level privileges. Administrator-level privileges are required to exploit this vulnerability. This vulnerability is due to improper validation of a file when it is read from system flash memory. An attacker could exploit this vulnerability by copying a crafted file to the disk0: file system of an affected device. A successful exploit could allow the attacker to execute arbitrary code on the affected device after the next reload of the device, which could alter system behavior. Because the injected code could persist across device reboots, Cisco has raised the Security Impact Rating (SIR) of this advisory from Medium to High.

CWE(s)
KEV Date Added
24 April 2024

Related Threats

Threat-Actor AttributionAI

ArcaneDoor (C0046)
Talos blog reports ArcaneDoor espionage campaign exploited this Cisco ASA/FTD persistence RCE (and related CVE) in perimeter devices.

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
T1059.002 AppleScript Execution
Adversaries may abuse AppleScript for execution.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
T1059.005 Visual Basic Execution
Adversaries may abuse Visual Basic (VB) for execution.
T1059.006 Python Execution
Adversaries may abuse Python commands and scripts for execution.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-20485Same product: Cisco Adaptive Security Appliance Software
CVE-2020-3580Same product: Cisco Adaptive Security Appliance Softwareboth on KEV
CVE-2026-20045Same vendor: Ciscoboth on KEV
CVE-2020-3259Same product: Cisco Adaptive Security Appliance Softwareboth on KEV
CVE-2018-0296Same product: Cisco Adaptive Security Appliance Softwareboth on KEV
CVE-2018-0101Same product: Cisco Adaptive Security Appliance Software
CVE-2014-2120Same product: Cisco Adaptive Security Appliance Softwareboth on KEV
CVE-2023-20063Same product: Cisco Secure Firewall Threat Defense
CVE-2022-22965Same vendor: Ciscoboth on KEV
CVE-2026-1340Shared CWE-94both on KEV

Affected Assets

cisco
adaptive security appliance software
9.12.1, 9.12.1.2, 9.12.1.3, 9.12.2, 9.12.2.1
cisco
secure firewall threat defense
6.2.3, 6.2.3.1, 6.2.3.10, 6.2.3.11, 6.2.3.12

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)
  • V1.3.1

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation finds code paths that accept and execute externally influenced strings.

Input validation directly stops untrusted data from being used to construct executable code without neutralization.

Least privilege limits the damage an injected code fragment can perform once executed.

Requiring documented secure development standards and tools enforces use of safe code-generation APIs and escaping.

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 mostly match
prevents

PR.PS-06's SDLC practices directly target injection flaws via secure coding and testing (mostly), yet as a single broad outcome it leaves many code-generation specifics unaddressed (partial).

PR.DS-10 none match
prevents

PR.DS-10 protects runtime data confidentiality/integrity but has no bearing on neutralizing externally influenced input during code generation, so neither direction shows any preventive effect.

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.

prevents

Banning unapproved code samples and unauthenticated web services, combined with secure-coding standards and SAST, prevents the dynamic generation or inclusion of attacker-supplied code.

none

Controls that restrict unauthorized or malicious code from being introduced via external networks or removable media limit opportunities for an attacker to inject and execute arbitrary code.

References