CVE-2026-82768: SGA1000 Path Traversal Vulnerability

CVE-2026-82768 Overview

CVE-2026-82768 is a path traversal vulnerability [CWE-23] affecting the Contec SGA1000 product. An attacker with FTP access to the device can traverse outside the intended directory to read or modify arbitrary files on the server. The flaw requires low privileges and no user interaction, and it is exploitable over the network through the product's FTP interface. Successful exploitation compromises the confidentiality and integrity of files stored on the affected device.

Critical Impact
An authenticated FTP user can view or alter arbitrary files on the SGA1000 device, enabling configuration tampering, disclosure of sensitive data, and potential downstream compromise of connected systems.

Affected Products

Contec SGA1000
See the Contec Security Information Document for the complete list of affected firmware versions
Refer to JVN Security Advisory JVNVU99009004 for coordinated disclosure details

Discovery Timeline

2026-09-14 - CVE-2026-82768 published to NVD
2026-09-16 - Last updated in NVD database

Technical Details for CVE-2026-82768

Vulnerability Analysis

The vulnerability is a path traversal weakness in the FTP service of the Contec SGA1000. The FTP handler does not properly canonicalize or restrict file path input supplied by authenticated clients. As a result, sequences such as ../ allow the client to escape the intended FTP root and reference files elsewhere on the device filesystem.

Because the attack surface is the FTP service, exploitation requires network reachability to the FTP port and valid credentials with at least low privileges. Once inside, an attacker can read sensitive files such as configuration, credentials, or firmware artifacts. The same primitive supports write operations, meaning arbitrary files can be overwritten to modify device behavior.

Root Cause

The root cause is improper limitation of a pathname to a restricted directory, classified under [CWE-23]. The FTP command processor accepts relative path components without validating that the resolved path remains within the permitted directory tree. Missing input sanitization on GET, PUT, and directory listing commands enables traversal beyond the FTP jail.

Attack Vector

An attacker authenticates to the FTP service exposed by the SGA1000 using any valid low-privileged account. The attacker then issues FTP commands that reference paths containing traversal sequences to reach files outside the intended directory. Files can be downloaded to disclose sensitive contents or uploaded to overwrite existing files on the device. No user interaction is required beyond the attacker's own FTP session.

Detailed technical information is available in the vendor advisory and coordinated disclosure notes referenced above. No public proof-of-concept exploit is currently listed for this issue.

Detection Methods for CVE-2026-82768

Indicators of Compromise

FTP session logs containing path components such as ../, ..\, or URL-encoded equivalents (%2e%2e%2f) in RETR, STOR, LIST, or CWD commands
Unexpected FTP STOR or DELE operations targeting configuration or system paths on the SGA1000
Successful FTP authentication events from source addresses outside expected management networks

Detection Strategies

Enable verbose FTP command logging on the SGA1000 and forward logs to a central SIEM for inspection
Alert on any FTP command whose argument contains traversal tokens or references paths outside the designated FTP root
Correlate FTP authentication events with subsequent file transfer volume anomalies to surface reconnaissance behavior

Monitoring Recommendations

Monitor network flows to TCP/21 and any configured FTP data ports on SGA1000 devices for unexpected clients
Track file integrity of critical configuration and firmware paths on the device where supported
Review authentication logs for brute-force patterns against FTP accounts on affected products

How to Mitigate CVE-2026-82768

Immediate Actions Required

Restrict network access to the SGA1000 FTP service to trusted management hosts using firewall or ACL rules
Disable the FTP service entirely if it is not required for operations
Rotate credentials for all FTP accounts on affected devices and enforce strong, unique passwords
Apply the fixed firmware released by Contec as soon as it is available for your deployment

Patch Information

Contec has published remediation guidance in the Contec Security Information Document. Coordinated disclosure details, including any fixed firmware versions and mitigation steps, are also available through JVN Security Advisory JVNVU99009004. Administrators should consult these advisories for the specific firmware image applicable to their SGA1000 model.

Workarounds

Place the SGA1000 behind a jump host or VPN so the FTP service is not reachable from untrusted networks
Replace FTP with a secure file transfer channel where the product supports it, or tunnel FTP through an encrypted transport
Remove or disable unused low-privileged FTP accounts to reduce the pool of usable credentials

bash

# Example firewall restriction limiting FTP access to a management subnet
iptables -A INPUT -p tcp --dport 21 -s 10.10.20.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 21 -j DROP