EXPOSURES › CVE-2026-109439
CVE-2026-109439
CRITICALLantronix XPress-DR and XPress-DR-I firmware through 8.1.0.0 lacks authentication on its UDP configuration protocol, allowing remote attackers to read and persistently overwrite device configuration without credentials.
The missing authentication on the UDP configuration protocol enables remote attackers to read live configuration data and rewrite device settings like IP addresses and serial-channel forwarding records, which persist across reboots. DIB organizations must ensure these end-of-life devices are patched or replaced, as unauthenticated remote configuration changes violate NIST 800-171 requirements for access control and system integrity. Failure to address this exposes networks to persistent tampering and unauthorized access.
Shame score — A missing authentication vulnerability on an unauthenticated UDP protocol is a fundamental design flaw that allows remote attackers to persistently alter device configuration without any credentials, representing a severe avoidable security oversight.
▸ RECOMMENDED ACTION Critical severity — schedule patching of the affected products.
Lantronix XPress-DR and XPress-DR-I (CoBos-family) firmware through 8.1.0.0 contains a missing authentication vulnerability that allows remote attackers to read and persistently overwrite device configuration by sending crafted frames to the unauthenticated UDP configuration protocol on port 30718. Attackers can send a type 0xF8 query to read live configuration data and a type 0xFD frame with exactly 0x78 body bytes to rewrite the device IP address and serial-channel forwarding records, causing changes to commit to EEPROM and persist across reboots. The XPress-DR product series reached end-of-life/end-of-support in February 2025.