CVE-2024-20329

Q: What is the severity of CVE-2024-20329?

CVE-2024-20329 has a CVSS score of 9.9 (CRITICAL). This critical vulnerability in Cisco ASA Software allows authenticated remote attackers to execute arbitrary operating system commands with root privileges via SSH. Attackers with limited user access can gain complete system control by exploiting insufficient input validation in the SSH subsystem. Organizations using affected Cisco ASA devices are at risk.

9.9 CRITICAL

Remote Code Execution

📋 TL;DR

This critical vulnerability in Cisco ASA Software allows authenticated remote attackers to execute arbitrary operating system commands with root privileges via SSH. Attackers with limited user access can gain complete system control by exploiting insufficient input validation in the SSH subsystem. Organizations using affected Cisco ASA devices are at risk.

💻 Affected Systems

Products:

Cisco Adaptive Security Appliance (ASA) Software

Versions: Multiple versions - check Cisco advisory for specific affected releases

Operating Systems: Cisco ASA OS

Default Config Vulnerable: ⚠️ Yes

Notes: Requires SSH access to the device with valid user credentials. Devices with SSH enabled and exposed to untrusted networks are particularly vulnerable.

📦 What is this software?

⚠️ Risk & Real-World Impact

🔴

Worst Case

Complete compromise of the ASA device, allowing attackers to install persistent backdoors, exfiltrate sensitive data, pivot to internal networks, and disrupt network operations.

🟠

Likely Case

Privilege escalation from limited SSH user to root access, enabling configuration changes, credential theft, and lateral movement within the network.

🟢

If Mitigated

Limited impact if proper network segmentation, least privilege access, and monitoring are implemented, though risk remains until patching.

🌐 Internet-Facing: HIGH

🏢 Internal Only: HIGH

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ✅ No

Complexity: LOW

Exploitation requires authenticated SSH access but is considered low complexity once credentials are obtained. No public exploit code is available at this time.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Check Cisco advisory for specific fixed releases

Vendor Advisory: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-ssh-rce-gRAuPEUF

Restart Required: Yes

Instructions:

1. Review Cisco advisory for affected versions. 2. Download and apply the appropriate fixed software release from Cisco. 3. Schedule maintenance window for device restart. 4. Verify patch application and functionality.

🔧 Temporary Workarounds

Restrict SSH Access

all

Limit SSH access to trusted management networks and specific source IP addresses

ssh 192.168.1.0 255.255.255.0 management
ssh 10.0.0.5 255.255.255.255 outside

Disable SSH if Not Required

all

Completely disable SSH access if not needed for device management

no ssh

🧯 If You Can't Patch

Implement strict network access controls to limit SSH connections to trusted management networks only
Enforce multi-factor authentication and strong password policies for SSH users, regularly rotate credentials

🔍 How to Verify

Check if Vulnerable:

Check ASA software version with 'show version' and compare against Cisco advisory for affected releases

Check Version:

show version | include Software

Verify Fix Applied:

Verify installed version matches fixed release from Cisco advisory and test SSH functionality

📡 Detection & Monitoring

Log Indicators:

Unusual SSH login patterns
Multiple failed SSH attempts followed by successful login
Execution of unusual CLI commands via SSH
Log entries showing privilege escalation attempts

Network Indicators:

SSH connections from unexpected source IPs
Unusual SSH session duration or data transfer
SSH traffic to management interfaces from non-management networks

SIEM Query:

source="asa" AND (event_type="ssh" OR protocol="ssh") AND (user="*" AND command="*" | stats count by src_ip, user, command)

📊 Metadata

CVE ID: CVE-2024-20329

CVSS v3 Score: 9.9 (CRITICAL)

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

CWE: CWE-146

Published: October 23, 2024

Last Updated: August 1, 2025

📋 TL;DR

💻 Affected Systems

📦 What is this software?

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

Adaptive Security Appliance Software by Cisco

⚠️ Risk & Real-World Impact

Worst Case

Likely Case

If Mitigated

🎯 Exploit Status

🛠️ Fix & Mitigation

✅ Official Fix

Instructions:

🔧 Temporary Workarounds

Restrict SSH Access

Disable SSH if Not Required

🧯 If You Can't Patch

🔍 How to Verify

Check if Vulnerable:

Check Version:

Verify Fix Applied:

📡 Detection & Monitoring

Log Indicators:

Network Indicators:

SIEM Query:

📊 Metadata

🔗 References

📤 Share & Export

🔗 Related Vulnerabilities