CVE-2024-33900

Executive Summary

CVE-2024-33900 affects KeePassXC version 2.7.7 and involves the recovery of cleartext credentials from a memory dump by an attacker with victim-level privileges. The vendor disputes the finding, stating that memory-management constraints make this unavoidable in the current and other realistic designs. The vulnerability is not a traditional code flaw but a design limitation where sensitive data remains in memory after use, allowing an attacker with local access to dump process memory and extract credentials. No official patch is provided, and the EPSS score is 0.0%, indicating low exploitation likelihood. However, the risk is significant in shared or compromised environments.

Supply Chain & Package Security

KeePassXC is a desktop application distributed via official repositories and package managers. No supply chain compromise is reported, but users should verify package signatures and sources.

CVSS Breakdown & Threat Level

• CVSS Score: 0.0 (No official vector assigned)
• Attack Vector: Local (attacker must have victim privileges)
• Attack Complexity: Low
• Privileges Required: Low (victim-level)
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: High (cleartext credentials exposed)
• Integrity Impact: None
• Availability Impact: None
• Threat Level: Medium (due to local access requirement but high impact)

Deep Dive & Mechanics

The vulnerability stems from KeePassXC's memory management. When a user unlocks a database, the master password and decrypted credentials are stored in process memory. Even after locking the database, remnants of these credentials may persist in memory pages that are not immediately zeroed. An attacker with local access (e.g., via malware, physical access, or a compromised account) can use tools like procdump or gcore to capture the KeePassXC process memory and then scan for patterns indicative of credentials (e.g., strings, base64-encoded data, or known headers). The vendor argues that zeroing memory immediately after use is impractical due to performance and compiler optimization constraints, making this a systemic issue rather than a simple bug.

Vulnerable vs. Patched Code

No patched version exists. The vulnerable behavior is inherent in KeePassXC 2.7.7. The vendor suggests that users rely on full-disk encryption and physical security to mitigate the risk. No code diff is available.

Exploitation & Lab Setup

Red Team

Prerequisites: Local access to the victim's machine with user-level privileges.

Steps:

1. Identify the KeePassXC process ID (PID):

   ps aux | grep keepassxc
   

2. Dump the process memory:

   gcore <PID>
   

   Or on Windows:

   procdump -ma <PID> keepassxc.dmp
   

3. Extract credentials from the memory dump:

   strings keepassxc.dmp | grep -E '^[A-Za-z0-9+/=]{20,}$' | head -20
   

   Or use a tool like volatility to analyze the dump for credential artifacts.

Note: No exploit-db code is available.

Blue Team

Detection:

• Monitor for memory dump tools (e.g., procdump, gcore, minidump) being executed against KeePassXC processes.
• Alert on unusual access to /proc/<PID>/mem or ProcessHacker activity.
• Use endpoint detection rules to flag memory dumping of password managers.

Mitigation:

• Enforce full-disk encryption (e.g., BitLocker, FileVault).
• Restrict local admin privileges.
• Use memory scanning tools to detect credential remnants.
• Consider using hardware-backed security modules (HSMs) or secure enclaves.

Indicators of Compromise (IOCs)

• Process Dump Files: keepassxc.dmp, *.dmp files in user directories.
• Tool Execution: procdump, gcore, volatility, strings run against KeePassXC.
• Memory Artifacts: Strings containing base64-like patterns or known KeePassXC headers in memory dumps.
• Network: No network IOCs (local attack only).

Detection Engineering

YARA Rule

rule CVE_2024_33900_KeePassXC_Memory_Dump {
    meta:
        description = "Detects memory dumps containing KeePassXC credential artifacts"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-33900"
    strings:
        $kp_header = "KeePassXC" ascii wide nocase
        $cred_pattern = /[A-Za-z0-9+/=]{40,}/ ascii
        $db_header = { 03 D9 A2 9A 65 FB 4B B5 } // KeePass database magic
    condition:
        ($kp_header or $db_header) and #cred_pattern > 5
}

Sigma Rule

title: Memory Dump of KeePassXC Process
id: 7b8f3c2a-1e5d-4a0f-9c6b-8d7e2f1a3b4c
status: experimental
description: Detects attempts to dump KeePassXC process memory using common tools
author: Valters IT
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\procdump.exe'
            - '\gcore.exe'
            - '\minidump.exe'
        CommandLine|contains:
            - 'keepassxc'
            - 'KeePassXC'
    condition: selection
falsepositives:
    - Legitimate debugging by authorized personnel
level: high

Suricata Rule

alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2024-33900 KeePassXC Memory Dump Exfiltration"; flow:to_server; content:"keepassxc"; nocase; pcre:"/[A-Za-z0-9+/=]{40,}/"; classtype:attempted-user; sid:1000001; rev:1;)

Remediation & Mitigation

• No official patch available. The vendor considers this a design limitation.
• Immediate Mitigation: Use full-disk encryption (e.g., LUKS, BitLocker) to protect memory dumps at rest.
• Short-term: Restrict local access to trusted users only. Disable core dumps for KeePassXC:

  ulimit -c 0
  

• Long-term: Consider using a password manager with hardware-backed memory protection (e.g., Apple Keychain, Windows Credential Manager). Monitor for updates from KeePassXC project.

Valters IT
DevSecOps & Cyber Threat Intelligence