CVE-2024-8688: PAN-OS Information Disclosure Vulnerability

CVE-2024-8688 Overview

An improper neutralization of matching symbols vulnerability in the Palo Alto Networks PAN-OS command line interface (CLI) enables authenticated administrators (including read-only administrators) with access to the CLI to read arbitrary files on the firewall. This vulnerability allows low-privilege administrators to access sensitive configuration data and system files beyond their intended authorization scope.

Critical Impact

Authenticated administrators with CLI access can read arbitrary files on PAN-OS firewalls, potentially exposing sensitive configuration data, credentials, and security policies.

Affected Products

• Palo Alto Networks PAN-OS (multiple versions)
• PAN-OS version 10.1.0 and related versions
• PAN-OS firewalls with CLI access enabled

Discovery Timeline

• September 11, 2024 - CVE-2024-8688 published to NVD
• October 3, 2024 - Last updated in NVD database

Technical Details for CVE-2024-8688

Vulnerability Analysis

This vulnerability is classified under CWE-155 (Improper Neutralization of Wildcards or Matching Symbols), indicating that the PAN-OS CLI fails to properly sanitize or neutralize special characters used in pattern matching operations. When authenticated administrators execute certain CLI commands, the system does not adequately validate input parameters that contain matching symbols or wildcards.

The local attack vector requires the attacker to have existing authenticated access to the device's CLI. Even read-only administrators, who should have limited system access, can exploit this flaw to read files outside their authorized scope. This represents a significant breakdown in the principle of least privilege.

Root Cause

The root cause lies in the improper handling of matching symbols within the PAN-OS CLI parser. When processing commands that accept file paths or patterns as arguments, the CLI interpreter fails to neutralize special characters that can be used to construct paths to unauthorized files. This allows attackers to craft inputs that traverse directory structures or match unintended file patterns.

Attack Vector

The attack requires local access through the CLI with valid administrator credentials. An attacker with read-only administrator privileges can exploit the improper symbol handling to construct commands that read sensitive system files, including configuration files, authentication data, and security policies. The vulnerability does not require any user interaction and can be executed with low attack complexity once CLI access is obtained.

The exploitation mechanism involves manipulating CLI command arguments to include matching symbols that bypass normal file access restrictions. Since even read-only administrators can execute this attack, organizations with multiple administrative tiers face elevated risk.

Detection Methods for CVE-2024-8688

Indicators of Compromise

• Unusual CLI command patterns containing wildcard or matching symbols in file path arguments
• Read-only administrators accessing files outside their normal operational scope
• Unexpected file access logs for sensitive system configuration files
• CLI session activity patterns indicating systematic file enumeration

Detection Strategies

• Monitor CLI session logs for commands containing unusual character sequences or pattern matching symbols
• Implement alerting for file access attempts by read-only administrators to sensitive system directories
• Review audit logs for repeated CLI command executions with varying path parameters
• Correlate administrative login events with subsequent file access patterns

Monitoring Recommendations

• Enable comprehensive CLI command logging on all PAN-OS devices
• Configure SIEM rules to detect anomalous file read patterns from administrative sessions
• Implement baseline analysis for normal administrator CLI behavior to identify deviations
• Set up alerts for access attempts to critical configuration files from non-superuser accounts

How to Mitigate CVE-2024-8688

Immediate Actions Required

• Review and restrict CLI access to only essential administrators
• Audit current read-only administrator accounts and assess necessity of CLI access
• Implement network segmentation to limit management plane access
• Monitor for signs of exploitation using the detection strategies outlined above

Patch Information

Palo Alto Networks has released security updates to address this vulnerability. Organizations should consult the Palo Alto Networks Security Advisory for specific version information and upgrade guidance. Apply the appropriate patches according to your PAN-OS version deployment.

Workarounds

• Restrict CLI access by removing unnecessary administrative accounts from CLI access groups
• Implement strict network access controls to limit which hosts can reach the management interface
• Consider disabling CLI access for read-only administrators where operationally feasible
• Use role-based access controls to minimize the number of accounts with CLI privileges

# Example: Review and restrict administrative CLI access
# Check current admin accounts with CLI access
show admins all

# Review authentication profiles and restrict CLI access
configure
set mgt-config users <username> permissions role-based custom profile <restricted-profile>
commit