CVE-2025-64389: Information Disclosure Vulnerability

CVE-2025-64389 Overview

CVE-2025-64389 is a cleartext transmission vulnerability [CWE-319] affecting the web server of an industrial IoT device. The web server exchanges sensitive information over an insecure protocol without encryption. An attacker positioned on the network path can intercept credentials, session tokens, or configuration data in transit. Public references link the issue to CIRCUTOR IoT gateway products and research published by Thales / S21sec and the HackRTU research team.

Critical Impact

Network-adjacent attackers can passively capture authentication credentials and sensitive device data, enabling full compromise of the affected industrial gateway and downstream operational technology assets.

Affected Products

• CIRCUTOR IoT industrial converter and gateway devices (referenced product D80010)
• Device web management interface served over an unencrypted protocol
• Deployments exposing the management interface to untrusted network segments

Discovery Timeline

• 2025-10-31 - CVE-2025-64389 published to the National Vulnerability Database (NVD)
• 2026-04-15 - Last updated in the NVD database

Technical Details for CVE-2025-64389

Vulnerability Analysis

The device exposes a web management interface that transmits sensitive data in cleartext. Authentication credentials, session identifiers, and configuration parameters traverse the network without transport-layer encryption. Any attacker capable of observing network traffic between an administrator and the device can recover these values directly from the wire.

The weakness is categorized under [CWE-319] Cleartext Transmission of Sensitive Information. Unlike memory-corruption or injection flaws, exploitation requires no malformed input. It depends only on access to the communication path. In industrial environments, that path frequently traverses shared switches, wireless segments, or remote-access infrastructure.

The EPSS data indicates a low probability of mass exploitation, but the impact on an individual targeted device is significant. Captured administrator credentials grant the attacker the same control over the device as a legitimate operator.

Root Cause

The root cause is the absence of Transport Layer Security (TLS) on the embedded web server. The device serves administrative pages and processes authentication form submissions over plain HTTP. No certificate-based encryption protects the session, and there is no enforced redirect to a secure channel.

Attack Vector

Exploitation requires network adjacency to the management traffic and a user interaction such as an administrator logging into the device. An attacker performing passive sniffing on a shared LAN segment, a compromised network device, or a man-in-the-middle position can capture credentials in cleartext. The attacker can then authenticate to the web interface and modify device configuration, alter relay or measurement logic, or pivot to other industrial systems. The vulnerability is described in prose in the published research; no exploit code is required beyond standard packet capture tooling.

Detection Methods for CVE-2025-64389

Indicators of Compromise

• Unexpected administrative logins to the device web interface from unfamiliar source IP addresses
• Configuration changes on the affected gateway with no corresponding change-management record
• Plain HTTP traffic on TCP/80 to device management interfaces observed in network captures
• ARP table anomalies on the management VLAN suggesting man-in-the-middle activity

Detection Strategies

• Inspect network flows for HTTP requests carrying Authorization, form-based credentials, or session cookies to industrial device IP ranges
• Run periodic TLS posture scans against device management interfaces and flag endpoints responding only on port 80
• Correlate device audit logs with authentication events from monitored administrative workstations to identify logins lacking a legitimate source

Monitoring Recommendations

• Forward web-server and authentication logs from the affected devices to a centralized log platform for retention and correlation
• Alert on logins outside approved maintenance windows or from outside the engineering subnet
• Monitor for new MAC-to-IP bindings on the management VLAN that could indicate ARP spoofing

How to Mitigate CVE-2025-64389

Immediate Actions Required

• Restrict access to the device web interface to a dedicated, isolated management VLAN with strict access control lists
• Require administrators to reach the device only through a jump host or VPN that enforces encrypted transport
• Rotate all credentials used on affected devices, assuming prior cleartext exposure on the network
• Disable the HTTP management interface where the device supports an alternative secure channel

Patch Information

No vendor patch is referenced in the published advisory data. Consult the CIRCUTOR IoT product page, the Thales Group security resource, and the HackRTU technical write-up for current vendor guidance and firmware updates. Apply firmware updates that introduce HTTPS support as soon as they are made available.

Workarounds

• Place the device behind a reverse proxy that terminates TLS and forwards only to the device over an isolated link
• Enforce port-security and 802.1X on switches serving device management traffic to limit sniffing opportunities
• Use out-of-band management networks physically separated from production OT and corporate traffic

# Example: restrict device web interface to a management subnet using iptables on an upstream gateway
iptables -A FORWARD -p tcp -d 192.0.2.10 --dport 80 -s 10.10.50.0/24 -j ACCEPT
iptables -A FORWARD -p tcp -d 192.0.2.10 --dport 80 -j DROP