CVE-2026-40005: Apache IoTDB Path Traversal Vulnerability

CVE-2026-40005 Overview

CVE-2026-40005 is a path traversal vulnerability [CWE-22] in Apache IoTDB, a time-series database platform used for Internet of Things (IoT) workloads. The flaw exists in an unsafe API that fails to properly validate pathname inputs. An attacker can leverage this weakness to write arbitrary files anywhere the IoTDB process has write permissions on the host filesystem. The issue affects Apache IoTDB from version 1.0.0 before 2.0.10. Upgrading to version 2.0.10 remediates the vulnerability.

Critical Impact
Remote unauthenticated attackers can write arbitrary files to any location writable by the IoTDB process, enabling code execution, configuration tampering, and system compromise.

Affected Products

Apache IoTDB 1.0.0 through 2.0.9
Apache IoTDB deployments exposing the vulnerable API over the network
Any environment where the IoTDB service account has broad filesystem write permissions

Discovery Timeline

2026-07-10 - CVE CVE-2026-40005 published to NVD
2026-07-10 - Last updated in NVD database

Technical Details for CVE-2026-40005

Vulnerability Analysis

The vulnerability resides in an Apache IoTDB API that accepts file path parameters without enforcing directory boundaries. The API writes attacker-controlled content to a location derived from user input. Because the pathname is not canonicalized or validated against an allow-listed base directory, traversal sequences such as ../ escape the intended storage directory. An attacker can drop payloads into system directories, application configuration paths, or scheduled task locations. Successful writes lead to remote code execution, persistence, and integrity loss across the host running the IoTDB process.

Root Cause

The root cause is improper limitation of a pathname to a restricted directory [CWE-22]. The affected API accepts a user-supplied path and passes it to file write routines without normalizing traversal sequences or verifying that the resolved path resides within an approved base directory. This class of flaw allows attackers to break out of the intended data directory and target arbitrary filesystem locations.

Attack Vector

The attack vector is network-based and requires no authentication or user interaction. An attacker submits a crafted request to the vulnerable API with a path parameter containing directory traversal sequences and payload content. The IoTDB process writes the file using its own permissions. Attackers commonly target Java classpath directories, cron job locations, SSH authorized_keys files, or web server document roots to achieve code execution or persistence.

No verified proof-of-concept code is publicly available. Refer to the Apache Mailing List Thread and the OpenWall OSS-Security Post for advisory details.

Detection Methods for CVE-2026-40005

Indicators of Compromise

Unexpected files appearing outside the configured IoTDB data directory, particularly in system paths, home directories, or service configuration folders
IoTDB API requests containing traversal sequences such as ../, ..\, encoded variants (%2e%2e%2f), or absolute paths in file-related parameters
New or modified files owned by the IoTDB service account in directories such as /etc, /root/.ssh, or Java library paths
Outbound connections from processes spawned after suspicious file writes by IoTDB

Detection Strategies

Inspect IoTDB access and application logs for API calls referencing path parameters with traversal patterns or absolute paths
Deploy file integrity monitoring (FIM) on directories writable by the IoTDB service account and on adjacent system directories
Correlate IoTDB request patterns with subsequent process creation events on the host to identify write-then-execute chains
Alert on IoTDB installations running versions between 1.0.0 and 2.0.9 via software inventory scans

Monitoring Recommendations

Enable verbose API request logging on IoTDB nodes and forward logs to a centralized SIEM for retention and correlation
Monitor filesystem write events initiated by the iotdb process user across all mounted volumes
Track parent-child process relationships originating from the IoTDB JVM to catch downstream execution

How to Mitigate CVE-2026-40005

Immediate Actions Required

Upgrade Apache IoTDB to version 2.0.10 or later, which remediates the path traversal flaw
Restrict network access to IoTDB API endpoints using firewalls or network segmentation until patching is complete
Audit the IoTDB host for unauthorized files created outside the configured data directory since deployment
Rotate credentials, SSH keys, and secrets accessible from the IoTDB host if compromise is suspected

Patch Information

Apache has released Apache IoTDB 2.0.10 containing the fix. Users running any version from 1.0.0 up to but not including 2.0.10 must upgrade. The vendor advisory is available on the Apache Mailing List Thread.

Workarounds

Run the IoTDB process under a dedicated low-privilege service account with write access limited to the IoTDB data directory
Apply mandatory access controls such as SELinux or AppArmor profiles that constrain IoTDB filesystem writes to approved paths
Place a reverse proxy or web application firewall (WAF) in front of the IoTDB API to block requests containing traversal sequences
Disable or block the affected unsafe API endpoint at the network layer where feasible until the upgrade is applied

bash

# Example: constrain IoTDB service account write access on Linux
# Create dedicated user and restrict data directory ownership
sudo useradd -r -s /usr/sbin/nologin iotdb
sudo chown -R iotdb:iotdb /var/lib/iotdb
sudo chmod 750 /var/lib/iotdb

# Example WAF rule pattern to block traversal in IoTDB API paths
# (adapt to your WAF syntax)
# SecRule ARGS "@rx (\.\./|\.\.\\|%2e%2e%2f|%2e%2e/)" \
#   "id:1040005,phase:2,deny,status:403,msg:'IoTDB path traversal attempt'"