CVE-2022-50932: Kyocera Command Center Path Traversal

CVE-2022-50932 Overview

Kyocera Command Center RX ECOSYS M2035dn contains a directory traversal vulnerability that allows unauthenticated attackers to read sensitive system files by manipulating file paths under the /js/ path. This vulnerability enables remote attackers to bypass access controls and retrieve critical configuration files from the underlying system without any authentication, potentially exposing sensitive credentials and system information.

Critical Impact
Unauthenticated remote attackers can access sensitive system files including /etc/passwd and /etc/shadow through path traversal, potentially compromising system credentials and enabling further attacks.

Affected Products

Kyocera Command Center RX
Kyocera ECOSYS M2035dn

Discovery Timeline

2026-01-13 - CVE CVE-2022-50932 published to NVD
2026-01-13 - Last updated in NVD database

Technical Details for CVE-2022-50932

Vulnerability Analysis

This directory traversal vulnerability (CWE-22) affects the Kyocera Command Center RX web interface, specifically within the /js/ path handling mechanism. The vulnerability arises from insufficient input validation when processing file path requests, allowing attackers to escape the intended directory structure using path traversal sequences.

The flaw enables unauthenticated remote attackers to read arbitrary files from the underlying file system. This is particularly concerning for network-attached devices like multifunction printers, which often contain configuration files with sensitive information including network credentials, LDAP configurations, and administrative passwords.

Root Cause

The root cause of this vulnerability is improper input validation in the web server component handling requests to the /js/ endpoint. The application fails to properly sanitize user-supplied path components, allowing directory traversal sequences (../) to escape the web root directory. Additionally, the application does not properly handle null-byte injection (%00), which allows attackers to bypass file extension restrictions by appending a null byte followed by a permitted extension like .jpg.

Attack Vector

The attack is network-based and requires no authentication or user interaction. Attackers can exploit this vulnerability by sending specially crafted HTTP requests to the vulnerable endpoint. The attack leverages multiple path traversal sequences (../../../../...) combined with null-byte injection to access files outside the intended web directory.

For example, an attacker could request paths such as /js/../../../../.../etc/passwd%00.jpg to retrieve the system's password file. The null byte effectively terminates the string processing, causing the server to ignore the .jpg extension while still passing any file extension validation checks.

Technical details and proof-of-concept information can be found in the Exploit-DB #50738 entry and the VulnCheck Advisory on Kyocera.

Detection Methods for CVE-2022-50932

Indicators of Compromise

HTTP requests containing path traversal sequences (../) targeting the /js/ endpoint
Requests with null-byte encoding (%00) attempting to bypass file extension filters
Access log entries showing requests for sensitive system files like /etc/passwd or /etc/shadow
Unusual patterns of file access attempts from external IP addresses to printer management interfaces

Detection Strategies

Monitor web server access logs for requests containing ../ sequences to the /js/ path
Implement web application firewall (WAF) rules to detect and block null-byte injection attempts
Configure intrusion detection systems to alert on path traversal patterns in HTTP traffic
Review network traffic to multifunction printer management interfaces for suspicious file access attempts

Monitoring Recommendations

Enable verbose logging on Kyocera Command Center RX web interfaces
Implement network segmentation to isolate printer management interfaces from untrusted networks
Deploy network monitoring solutions to detect anomalous traffic patterns to printer devices
Regularly audit access logs for evidence of exploitation attempts

How to Mitigate CVE-2022-50932

Immediate Actions Required

Restrict network access to Kyocera Command Center RX management interfaces to trusted administrative networks only
Implement firewall rules to block external access to printer management web interfaces
Deploy a web application firewall (WAF) with rules to block path traversal and null-byte injection attempts
Conduct an audit of potentially affected devices to determine if exploitation has occurred

Patch Information

Consult the Kyocera Product Information page for firmware updates and security patches. Contact Kyocera support for guidance on obtaining and applying the latest firmware that addresses this vulnerability.

Workarounds

Place affected devices behind a network firewall and restrict access to management interfaces
Implement network segmentation to isolate printer management traffic from general network access
Use VPN or jump hosts for administrative access to printer management interfaces
Disable web-based management interfaces if not required for operations

bash

# Example firewall configuration to restrict access to printer management interface
# Allow access only from trusted management subnet
iptables -A INPUT -p tcp --dport 80 -s 192.168.10.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 192.168.10.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP