CVE-2025-34187 Overview
CVE-2025-34187 affects Ilevia EVE X1 and X5 Server firmware versions ≤ 4.7.18.0.eden. The flaw stems from a misconfiguration in the sudoers file that allows passwordless execution of certain Bash scripts. Attackers who can write to those scripts, or who reach them through command injection, replace their contents with malicious payloads. Because sudo runs the scripts as root, the result is full remote privilege escalation and complete system compromise. The weakness maps to [CWE-78] (OS Command Injection) and impacts building automation deployments that expose the EVE web interface.
Critical Impact
Network-reachable attackers gain unauthenticated root access on EVE X1/X5 servers controlling smart home and building automation infrastructure.
Affected Products
- Ilevia EVE X1 Server firmware versions ≤ 4.7.18.0.eden
- Ilevia EVE X5 Server firmware versions ≤ 4.7.18.0.eden
- Ilevia EVE X1 Server hardware appliance
Discovery Timeline
- 2025-09-16 - CVE-2025-34187 published to the National Vulnerability Database
- 2025-09-25 - Last updated in NVD database
Technical Details for CVE-2025-34187
Vulnerability Analysis
The EVE X1/X5 Server ships with a sudoers policy that grants NOPASSWD execution rights to specific Bash scripts. The web service account, which serves the device's management interface, is permitted to invoke these scripts through sudo without authentication. This configuration converts any script-content control into root code execution.
The root account on the EVE server controls the KNX bus, scenes, and automation logic. Once an attacker gains root, they pivot from web access to full control of physical building systems.
Root Cause
The vulnerability has two contributing defects. First, the sudoers entry grants passwordless sudo to scripts that are writable, or invokable with attacker-controlled arguments, by lower-privileged accounts. Second, the web-facing components do not sanitize input passed to shell handlers, enabling command injection ([CWE-78]) that reaches the sudo-invoked scripts.
When a low-privileged web user modifies one of the listed scripts or injects shell metacharacters into its arguments, the subsequent sudo call executes the attacker payload with uid=0.
Attack Vector
The attack vector is network-based and requires no authentication or user interaction. An attacker reaches the EVE web management endpoint over HTTP or HTTPS and submits a crafted request to a vulnerable handler. The handler either writes attacker-supplied content into one of the sudo-allowlisted Bash scripts, or injects shell metacharacters into the command line passed to that script. The web process then invokes sudo on the modified script, yielding a reverse root shell. Public technical analysis is available in the VulnCheck Advisory on Ilevia and the Zero Science Vulnerability Report.
// No verified exploit code is published in NVD references.
// Refer to the VulnCheck and Zero Science advisories linked above
// for proof-of-concept details and request payloads.
Detection Methods for CVE-2025-34187
Indicators of Compromise
- Unexpected modifications to Bash scripts listed in /etc/sudoers or /etc/sudoers.d/ on the EVE appliance
- New processes spawned as root whose parent is the EVE web service account
- Outbound TCP connections from the EVE server to attacker-controlled hosts, consistent with reverse-shell behavior
- HTTP requests to EVE management endpoints containing shell metacharacters such as ;, |, `, or $( in parameters
Detection Strategies
- Monitor auth.log and sudo audit records for NOPASSWD invocations originating from the web service user
- Baseline the SHA-256 hashes of all scripts referenced by the sudoers policy and alert on drift
- Inspect web server access logs for POST or GET requests targeting administrative endpoints from unauthenticated sources
Monitoring Recommendations
- Forward EVE server syslog and authentication events to a central SIEM for correlation
- Track egress traffic from building automation VLANs and alert on connections to non-approved external IPs
- Enable file integrity monitoring on /etc/sudoers, /etc/sudoers.d/, and any Bash script paths invoked via sudo
How to Mitigate CVE-2025-34187
Immediate Actions Required
- Remove EVE X1/X5 Server management interfaces from the public internet and restrict access to trusted management VLANs
- Place the appliance behind a firewall that allows inbound connections only from authorized installer workstations
- Audit /etc/sudoers and remove NOPASSWD entries for scripts writable by non-root accounts
- Rotate any credentials, KNX keys, or API tokens stored on potentially exposed devices
Patch Information
Ilevia has not published a vendor advisory linked in the NVD record at the time of writing. Operators should contact Ilevia support and consult the VulnCheck Advisory on Ilevia and Packet Storm File Release for the latest remediation status. Versions after 4.7.18.0.eden, when released, should be deployed across all affected units.
Workarounds
- Restrict the sudoers policy so that scripts callable with NOPASSWD are owned by root and not writable by any other account
- Disable remote access to the EVE web management interface and require VPN connectivity for administrators
- Apply network segmentation between building automation devices and corporate or guest networks
- Deploy a reverse proxy with strict input validation in front of the EVE server to block shell metacharacters in request parameters
# Verify and harden sudoers entries on the EVE appliance
sudo visudo -c
sudo grep -R "NOPASSWD" /etc/sudoers /etc/sudoers.d/
# Ensure listed scripts are root-owned and not group/world writable
sudo chown root:root /path/to/allowlisted/script.sh
sudo chmod 755 /path/to/allowlisted/script.sh
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
