CVE-2024-3829: Qdrant Path Traversal Vulnerability

CVE-2024-3829 Overview

CVE-2024-3829 is a symlink attack vulnerability in Qdrant, an open-source vector database, affecting version 1.9.0-dev. The vulnerability exists in the snapshot recovery process, where attackers can manipulate snapshot files to include symbolic links. This allows for both arbitrary file read and arbitrary file write operations on the underlying server filesystem. By crafting malicious snapshot files containing symlinks pointing to sensitive system files, an attacker can read confidential data or overwrite critical files, potentially leading to a complete system takeover.

Critical Impact

This vulnerability allows unauthenticated remote attackers to read and write arbitrary files on the server through malicious snapshot manipulation, potentially resulting in full system compromise.

Affected Products

• Qdrant versions prior to v1.9.0
• Qdrant v1.9.0-dev development builds
• Systems running Qdrant with snapshot recovery functionality enabled

Discovery Timeline

• 2024-06-03 - CVE-2024-3829 published to NVD
• 2025-10-15 - Last updated in NVD database

Technical Details for CVE-2024-3829

Vulnerability Analysis

The vulnerability resides in Qdrant's snapshot recovery mechanism, which fails to properly validate or sanitize symbolic links within snapshot archives. When a user or automated process restores a snapshot, the system processes the archive contents without checking whether any files are actually symlinks pointing outside the intended directory structure.

This lack of validation creates two distinct attack scenarios. For arbitrary file read, an attacker can craft a snapshot containing a symlink that points to a target file (e.g., /etc/passwd, configuration files, or database credentials). When the snapshot is processed, the symlink is followed, and the contents of the target file become accessible through the normal snapshot data retrieval mechanisms.

For arbitrary file write, the attacker includes both a symlink and a corresponding payload file in the snapshot's directory structure. During recovery, the symlink is created first, and subsequently, the payload file is written to the location the symlink points to, effectively allowing the attacker to write arbitrary content to any file the Qdrant process has permissions to modify.

Root Cause

The root cause is classified under CWE-59 (Improper Link Resolution Before File Access). The snapshot recovery code does not verify whether entries in the snapshot archive are regular files or symbolic links before processing them. This improper handling of symlinks allows path traversal and arbitrary file system access outside the intended snapshot directory boundaries.

Attack Vector

The attack can be executed remotely over the network without authentication. An attacker needs the ability to upload or trigger the recovery of a malicious snapshot file. The attack flow involves:

1. Creating a crafted snapshot archive containing malicious symlinks
2. Uploading the snapshot to the target Qdrant instance or triggering recovery of an externally-hosted malicious snapshot
3. Upon snapshot recovery, the symlinks are processed, allowing file read or write operations
4. Exfiltrating sensitive data or writing malicious content to achieve further compromise

The vulnerability is particularly dangerous because it requires no user interaction and can be exploited with low attack complexity once an attacker can influence the snapshot recovery process.

Detection Methods for CVE-2024-3829

Indicators of Compromise

• Unexpected symbolic links appearing in Qdrant's storage or snapshot directories
• Unusual file access patterns originating from the Qdrant process, especially to sensitive system files
• Modified system files or configuration files with timestamps correlating to snapshot recovery operations
• Log entries showing snapshot recovery operations from untrusted or external sources

Detection Strategies

• Monitor file system operations from the Qdrant process for symlink creation or access to files outside expected directories
• Implement file integrity monitoring on critical system files to detect unauthorized modifications
• Audit snapshot recovery logs for suspicious activity, particularly recoveries from unknown sources
• Deploy application-level monitoring to track snapshot upload and recovery API calls

Monitoring Recommendations

• Enable verbose logging for Qdrant snapshot operations and forward logs to a SIEM for analysis
• Set up alerts for file access attempts outside the Qdrant data directory by the Qdrant process
• Monitor network traffic for large data exfiltration patterns that may indicate sensitive file theft
• Regularly audit the contents of snapshot directories for unexpected symlinks or file structures

How to Mitigate CVE-2024-3829

Immediate Actions Required

• Upgrade Qdrant to version v1.9.0 or later immediately
• Restrict snapshot upload and recovery functionality to trusted administrators only
• Audit existing snapshots for any suspicious symlinks or unexpected file structures
• Review access logs for any indication of exploitation prior to patching

Patch Information

The vulnerability has been fixed in Qdrant version v1.9.0. The fix is documented in the GitHub commit ee7a31ec3459a6a4219200234615c1817ab82260. Organizations should upgrade to v1.9.0 or later as soon as possible. Additional details about the vulnerability discovery can be found at the Huntr bounty listing.

Workarounds

• Disable snapshot recovery functionality if not required for operations until the patch can be applied
• Implement network segmentation to restrict access to Qdrant's snapshot management APIs
• Run Qdrant with minimal file system permissions to limit the impact of potential exploitation
• Use a read-only file system for sensitive directories that should not be modified by the Qdrant process

# Configuration example: Restrict Qdrant process permissions
# Run Qdrant with a dedicated user with minimal privileges
useradd -r -s /bin/false qdrant-service
chown -R qdrant-service:qdrant-service /opt/qdrant/data

# Restrict write access to only necessary directories
chmod 755 /opt/qdrant
chmod 700 /opt/qdrant/data
chmod 700 /opt/qdrant/snapshots

# Use systemd to enforce additional restrictions
# Add to qdrant.service:
# [Service]
# ProtectSystem=strict
# ProtectHome=true
# NoNewPrivileges=true
# ReadWritePaths=/opt/qdrant/data /opt/qdrant/snapshots